mirror of
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d9c989fa25
The Plan 9 tools assume that long is 32 bits. We converted all instances of long to int32 when importing the code but missed the print formats. Because int32 is always int on the compilers we use, it is never correct to use %lux, %ld, etc. Convert to %ux, %d, etc. (It matters because on 64-bit gcc, long is 64 bits, so we were printing 32-bit quantities with 64-bit formats.) R=ken2 CC=golang-dev https://golang.org/cl/2491041
641 lines
11 KiB
C
641 lines
11 KiB
C
// Inferno utils/5c/mul.c
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// http://code.google.com/p/inferno-os/source/browse/utils/5c/mul.c
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//
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// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
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// Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
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// Portions Copyright © 1997-1999 Vita Nuova Limited
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// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
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// Portions Copyright © 2004,2006 Bruce Ellis
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// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
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// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
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// Portions Copyright © 2009 The Go Authors. All rights reserved.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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#include "gc.h"
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/*
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* code sequences for multiply by constant.
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* [a-l][0-3]
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* lsl $(A-'a'),r0,r1
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* [+][0-7]
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* add r0,r1,r2
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* [-][0-7]
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* sub r0,r1,r2
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*/
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static int maxmulops = 3; /* max # of ops to replace mul with */
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static int multabp;
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static int32 mulval;
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static char* mulcp;
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static int32 valmax;
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static int shmax;
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static int docode(char *hp, char *cp, int r0, int r1);
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static int gen1(int len);
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static int gen2(int len, int32 r1);
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static int gen3(int len, int32 r0, int32 r1, int flag);
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enum
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{
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SR1 = 1<<0, /* r1 has been shifted */
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SR0 = 1<<1, /* r0 has been shifted */
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UR1 = 1<<2, /* r1 has not been used */
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UR0 = 1<<3, /* r0 has not been used */
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};
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Multab*
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mulcon0(int32 v)
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{
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int a1, a2, g;
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Multab *m, *m1;
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char hint[10];
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if(v < 0)
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v = -v;
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/*
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* look in cache
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*/
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m = multab;
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for(g=0; g<nelem(multab); g++) {
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if(m->val == v) {
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if(m->code[0] == 0)
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return 0;
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return m;
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}
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m++;
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}
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/*
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* select a spot in cache to overwrite
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*/
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multabp++;
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if(multabp < 0 || multabp >= nelem(multab))
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multabp = 0;
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m = multab+multabp;
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m->val = v;
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mulval = v;
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/*
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* look in execption hint table
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*/
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a1 = 0;
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a2 = hintabsize;
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for(;;) {
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if(a1 >= a2)
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goto no;
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g = (a2 + a1)/2;
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if(v < hintab[g].val) {
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a2 = g;
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continue;
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}
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if(v > hintab[g].val) {
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a1 = g+1;
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continue;
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}
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break;
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}
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if(docode(hintab[g].hint, m->code, 1, 0))
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return m;
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print("multiply table failure %d\n", v);
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m->code[0] = 0;
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return 0;
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no:
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/*
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* try to search
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*/
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hint[0] = 0;
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for(g=1; g<=maxmulops; g++) {
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if(g >= maxmulops && v >= 65535)
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break;
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mulcp = hint+g;
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*mulcp = 0;
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if(gen1(g)) {
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if(docode(hint, m->code, 1, 0))
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return m;
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print("multiply table failure %d\n", v);
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break;
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}
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}
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/*
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* try a recur followed by a shift
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*/
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g = 0;
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while(!(v & 1)) {
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g++;
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v >>= 1;
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}
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if(g) {
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m1 = mulcon0(v);
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if(m1) {
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strcpy(m->code, m1->code);
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sprint(strchr(m->code, 0), "%c0", g+'a');
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return m;
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}
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}
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m->code[0] = 0;
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return 0;
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}
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static int
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docode(char *hp, char *cp, int r0, int r1)
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{
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int c, i;
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c = *hp++;
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*cp = c;
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cp += 2;
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switch(c) {
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default:
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c -= 'a';
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if(c < 1 || c >= 30)
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break;
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for(i=0; i<4; i++) {
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switch(i) {
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case 0:
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if(docode(hp, cp, r0<<c, r1))
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goto out;
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break;
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case 1:
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if(docode(hp, cp, r1<<c, r1))
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goto out;
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break;
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case 2:
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if(docode(hp, cp, r0, r0<<c))
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goto out;
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break;
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case 3:
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if(docode(hp, cp, r0, r1<<c))
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goto out;
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break;
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}
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}
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break;
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case '+':
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for(i=0; i<8; i++) {
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cp[-1] = i+'0';
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switch(i) {
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case 1:
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if(docode(hp, cp, r0+r1, r1))
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goto out;
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break;
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case 5:
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if(docode(hp, cp, r0, r0+r1))
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goto out;
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break;
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}
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}
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break;
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case '-':
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for(i=0; i<8; i++) {
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cp[-1] = i+'0';
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switch(i) {
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case 1:
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if(docode(hp, cp, r0-r1, r1))
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goto out;
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break;
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case 2:
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if(docode(hp, cp, r1-r0, r1))
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goto out;
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break;
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case 5:
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if(docode(hp, cp, r0, r0-r1))
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goto out;
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break;
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case 6:
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if(docode(hp, cp, r0, r1-r0))
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goto out;
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break;
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}
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}
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break;
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case 0:
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if(r0 == mulval)
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return 1;
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}
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return 0;
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out:
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cp[-1] = i+'0';
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return 1;
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}
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static int
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gen1(int len)
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{
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int i;
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for(shmax=1; shmax<30; shmax++) {
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valmax = 1<<shmax;
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if(valmax >= mulval)
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break;
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}
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if(mulval == 1)
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return 1;
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len--;
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for(i=1; i<=shmax; i++)
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if(gen2(len, 1<<i)) {
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*--mulcp = 'a'+i;
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return 1;
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}
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return 0;
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}
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static int
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gen2(int len, int32 r1)
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{
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int i;
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if(len <= 0) {
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if(r1 == mulval)
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return 1;
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return 0;
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}
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len--;
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if(len == 0)
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goto calcr0;
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if(gen3(len, r1, r1+1, UR1)) {
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i = '+';
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goto out;
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}
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if(gen3(len, r1-1, r1, UR0)) {
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i = '-';
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goto out;
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}
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if(gen3(len, 1, r1+1, UR1)) {
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i = '+';
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goto out;
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}
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if(gen3(len, 1, r1-1, UR1)) {
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i = '-';
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goto out;
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}
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return 0;
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calcr0:
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if(mulval == r1+1) {
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i = '+';
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goto out;
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}
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if(mulval == r1-1) {
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i = '-';
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goto out;
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}
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return 0;
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out:
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*--mulcp = i;
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return 1;
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}
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static int
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gen3(int len, int32 r0, int32 r1, int flag)
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{
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int i, f1, f2;
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int32 x;
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if(r0 <= 0 ||
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r0 >= r1 ||
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r1 > valmax)
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return 0;
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len--;
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if(len == 0)
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goto calcr0;
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if(!(flag & UR1)) {
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f1 = UR1|SR1;
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for(i=1; i<=shmax; i++) {
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x = r0<<i;
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if(x > valmax)
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break;
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if(gen3(len, r0, x, f1)) {
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i += 'a';
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goto out;
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}
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}
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}
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if(!(flag & UR0)) {
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f1 = UR1|SR1;
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for(i=1; i<=shmax; i++) {
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x = r1<<i;
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if(x > valmax)
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break;
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if(gen3(len, r1, x, f1)) {
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i += 'a';
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goto out;
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}
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}
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}
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if(!(flag & SR1)) {
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f1 = UR1|SR1|(flag&UR0);
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for(i=1; i<=shmax; i++) {
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x = r1<<i;
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if(x > valmax)
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break;
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if(gen3(len, r0, x, f1)) {
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i += 'a';
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goto out;
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}
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}
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}
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if(!(flag & SR0)) {
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f1 = UR0|SR0|(flag&(SR1|UR1));
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f2 = UR1|SR1;
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if(flag & UR1)
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f2 |= UR0;
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if(flag & SR1)
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f2 |= SR0;
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for(i=1; i<=shmax; i++) {
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x = r0<<i;
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if(x > valmax)
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break;
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if(x > r1) {
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if(gen3(len, r1, x, f2)) {
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i += 'a';
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goto out;
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}
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} else
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if(gen3(len, x, r1, f1)) {
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i += 'a';
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goto out;
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}
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}
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}
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x = r1+r0;
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if(gen3(len, r0, x, UR1)) {
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i = '+';
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goto out;
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}
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if(gen3(len, r1, x, UR1)) {
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i = '+';
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goto out;
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}
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x = r1-r0;
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if(gen3(len, x, r1, UR0)) {
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i = '-';
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goto out;
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}
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if(x > r0) {
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if(gen3(len, r0, x, UR1)) {
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i = '-';
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goto out;
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}
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} else
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if(gen3(len, x, r0, UR0)) {
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i = '-';
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goto out;
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}
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return 0;
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calcr0:
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f1 = flag & (UR0|UR1);
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if(f1 == UR1) {
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for(i=1; i<=shmax; i++) {
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x = r1<<i;
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if(x >= mulval) {
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if(x == mulval) {
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i += 'a';
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goto out;
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}
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break;
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}
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}
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}
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if(mulval == r1+r0) {
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i = '+';
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goto out;
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}
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if(mulval == r1-r0) {
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i = '-';
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goto out;
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}
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return 0;
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out:
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*--mulcp = i;
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return 1;
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}
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/*
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* hint table has numbers that
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* the search algorithm fails on.
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* <1000:
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* all numbers
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* <5000:
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* ÷ by 5
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* <10000:
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* ÷ by 50
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* <65536:
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* ÷ by 250
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*/
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Hintab hintab[] =
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{
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683, "b++d+e+",
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687, "b+e++e-",
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691, "b++d+e+",
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731, "b++d+e+",
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811, "b++d+i+",
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821, "b++e+e+",
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843, "b+d++e+",
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851, "b+f-+e-",
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853, "b++e+e+",
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877, "c++++g-",
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933, "b+c++g-",
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981, "c-+e-d+",
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1375, "b+c+b+h-",
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1675, "d+b++h+",
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2425, "c++f-e+",
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2675, "c+d++f-",
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2750, "b+d-b+h-",
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2775, "c-+g-e-",
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3125, "b++e+g+",
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3275, "b+c+g+e+",
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3350, "c++++i+",
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3475, "c-+e-f-",
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3525, "c-+d+g-",
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3625, "c-+e-j+",
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3675, "b+d+d+e+",
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3725, "b+d-+h+",
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3925, "b+d+f-d-",
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4275, "b+g++e+",
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4325, "b+h-+d+",
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4425, "b+b+g-j-",
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4525, "b+d-d+f+",
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4675, "c++d-g+",
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4775, "b+d+b+g-",
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4825, "c+c-+i-",
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4850, "c++++i-",
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4925, "b++e-g-",
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4975, "c+f++e-",
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5500, "b+g-c+d+",
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6700, "d+b++i+",
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9700, "d++++j-",
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11000, "b+f-c-h-",
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11750, "b+d+g+j-",
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12500, "b+c+e-k+",
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13250, "b+d+e-f+",
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13750, "b+h-c-d+",
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14250, "b+g-c+e-",
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14500, "c+f+j-d-",
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14750, "d-g--f+",
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16750, "b+e-d-n+",
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17750, "c+h-b+e+",
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18250, "d+b+h-d+",
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18750, "b+g-++f+",
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19250, "b+e+b+h+",
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19750, "b++h--f-",
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20250, "b+e-l-c+",
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20750, "c++bi+e-",
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21250, "b+i+l+c+",
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22000, "b+e+d-g-",
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22250, "b+d-h+k-",
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22750, "b+d-e-g+",
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23250, "b+c+h+e-",
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23500, "b+g-c-g-",
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23750, "b+g-b+h-",
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24250, "c++g+m-",
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24750, "b+e+e+j-",
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25000, "b++dh+g+",
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25250, "b+e+d-g-",
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25750, "b+e+b+j+",
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26250, "b+h+c+e+",
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26500, "b+h+c+g+",
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26750, "b+d+e+g-",
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27250, "b+e+e+f+",
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27500, "c-i-c-d+",
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27750, "b+bd++j+",
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28250, "d-d-++i-",
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28500, "c+c-h-e-",
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29000, "b+g-d-f+",
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29500, "c+h+++e-",
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29750, "b+g+f-c+",
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30250, "b+f-g-c+",
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33500, "c-f-d-n+",
|
|
33750, "b+d-b+j-",
|
|
34250, "c+e+++i+",
|
|
35250, "e+b+d+k+",
|
|
35500, "c+e+d-g-",
|
|
35750, "c+i-++e+",
|
|
36250, "b+bh-d+e+",
|
|
36500, "c+c-h-e-",
|
|
36750, "d+e--i+",
|
|
37250, "b+g+g+b+",
|
|
37500, "b+h-b+f+",
|
|
37750, "c+be++j-",
|
|
38500, "b+e+b+i+",
|
|
38750, "d+i-b+d+",
|
|
39250, "b+g-l-+d+",
|
|
39500, "b+g-c+g-",
|
|
39750, "b+bh-c+f-",
|
|
40250, "b+bf+d+g-",
|
|
40500, "b+g-c+g+",
|
|
40750, "c+b+i-e+",
|
|
41250, "d++bf+h+",
|
|
41500, "b+j+c+d-",
|
|
41750, "c+f+b+h-",
|
|
42500, "c+h++g+",
|
|
42750, "b+g+d-f-",
|
|
43250, "b+l-e+d-",
|
|
43750, "c+bd+h+f-",
|
|
44000, "b+f+g-d-",
|
|
44250, "b+d-g--f+",
|
|
44500, "c+e+c+h+",
|
|
44750, "b+e+d-h-",
|
|
45250, "b++g+j-g+",
|
|
45500, "c+d+e-g+",
|
|
45750, "b+d-h-e-",
|
|
46250, "c+bd++j+",
|
|
46500, "b+d-c-j-",
|
|
46750, "e-e-b+g-",
|
|
47000, "b+c+d-j-",
|
|
47250, "b+e+e-g-",
|
|
47500, "b+g-c-h-",
|
|
47750, "b+f-c+h-",
|
|
48250, "d--h+n-",
|
|
48500, "b+c-g+m-",
|
|
48750, "b+e+e-g+",
|
|
49500, "c-f+e+j-",
|
|
49750, "c+c+g++f-",
|
|
50000, "b+e+e+k+",
|
|
50250, "b++i++g+",
|
|
50500, "c+g+f-i+",
|
|
50750, "b+e+d+k-",
|
|
51500, "b+i+c-f+",
|
|
51750, "b+bd+g-e-",
|
|
52250, "b+d+g-j+",
|
|
52500, "c+c+f+g+",
|
|
52750, "b+c+e+i+",
|
|
53000, "b+i+c+g+",
|
|
53500, "c+g+g-n+",
|
|
53750, "b+j+d-c+",
|
|
54250, "b+d-g-j-",
|
|
54500, "c-f+e+f+",
|
|
54750, "b+f-+c+g+",
|
|
55000, "b+g-d-g-",
|
|
55250, "b+e+e+g+",
|
|
55500, "b+cd++j+",
|
|
55750, "b+bh-d-f-",
|
|
56250, "c+d-b+j-",
|
|
56500, "c+d+c+i+",
|
|
56750, "b+e+d++h-",
|
|
57000, "b+d+g-f+",
|
|
57250, "b+f-m+d-",
|
|
57750, "b+i+c+e-",
|
|
58000, "b+e+d+h+",
|
|
58250, "c+b+g+g+",
|
|
58750, "d-e-j--e+",
|
|
59000, "d-i-+e+",
|
|
59250, "e--h-m+",
|
|
59500, "c+c-h+f-",
|
|
59750, "b+bh-e+i-",
|
|
60250, "b+bh-e-e-",
|
|
60500, "c+c-g-g-",
|
|
60750, "b+e-l-e-",
|
|
61250, "b+g-g-c+",
|
|
61750, "b+g-c+g+",
|
|
62250, "f--+c-i-",
|
|
62750, "e+f--+g+",
|
|
64750, "b+f+d+p-",
|
|
};
|
|
int hintabsize = nelem(hintab);
|