99 lines
2.0 KiB
C
99 lines
2.0 KiB
C
#include <string.h>
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#include <malloc.h>
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#include "lceb.h"
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static char *combs[1024]; /* should be dynamic */
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static int ncombs=0;
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void print_comb(n)
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int n;
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{
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printf("comb %d/%d=[%s]\n", n, ncombs, combs[n]);
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}
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void print_combs()
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{
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int i;
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printf("op combs: ");
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for (i=0; i<ncombs; ++i)
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printf("%s ", combs[i]);
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putchar('\n');
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}
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static unsigned n_combine(nops, len)
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int nops, len;
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{
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int result = 1;
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while(len > 0){
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if(len & 1)
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result *= nops;
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nops *= nops;
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len >>=1;
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}
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return result;
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}
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static char *combine(ops, len, n)
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char *ops; /* string to combine */
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int len; /* len of result */
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int n; /* iteration # */
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{
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static char *res=NULL;
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static int len_ops;
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int i;
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if (!res) { // 1st call
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len_ops=strlen(ops);
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res=malloc(len * sizeof(char) + 1);
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}
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for(i=0; i<len; ++i){
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res[len -i -1] = ops[n % len_ops];
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n /= len_ops;
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}
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return res;
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}
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void gen_combinations(nops)
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int nops;
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{
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char *ops="+-*/";
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int i, n_combs;
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int len_ops=strlen(ops);
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n_combs=n_combine(len_ops, nops);
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//printf("gen: n=%d\n", n_combs);
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for (i=0; i<n_combs; ++i) {
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combs[ncombs]=strdup(combine(ops, nops, i));
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ncombs++;
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}
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}
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int n_combs()
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{
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return ncombs;
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}
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char *nth_comb(n)
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int n;
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{
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return combs[n];
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}
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#ifdef STANDALONE
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int main(ac, av)
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int ac;
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char **av;
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{
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char *ops="+-*/", *p;
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int len_ops=strlen(ops);
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int i, j, nops, ncombs;
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nops=atoi(*(av+1));
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ncombs=n_combine(len_ops, nops);
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printf("# operators combinations : %d\nlist = ", ncombs);
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for (i=0; i<ncombs; ++i) {
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p=combine(ops, nops, i);
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printf("[%s]\n", p);
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//for (j=0; j<4; ++j)
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// distribute(j, p);
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//printf("\n");
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}
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}
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#endif
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