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/*
ID: mytbk921
LANG: C
TASK: hamming
*/
#include <stdio.h>
typedef unsigned char u8;
static unsigned
popcount(unsigned x)
{
unsigned c = 0;
while (x) {
if (x&1) c++;
x >>= 1;
}
return c;
}
static unsigned
hamdist(unsigned x, unsigned y)
{
return popcount(x^y);
}
u8 s[64];
int N, B, D;
int search(int i)
{
int t, j;
if (i==N) return 1;
for (t=s[i-1]+1; t<(1<<B); t++) {
for (j=0; j<i; j++) {
if (hamdist(s[j], t)<D)
break;
}
if (j==i) {
s[j] = t;
if (search(i+1))
return 1;
}
}
/* all searched */
return 0;
}
int main()
{
int i;
FILE *fin = fopen("hamming.in", "r");
FILE *fout = fopen("hamming.out", "w");
fscanf(fin, "%d%d%d", &N, &B, &D);
fclose(fin);
s[0] = 0;
if (search(1)) {
for (i=0; i<N; i++) {
if (i%10==0) {
if (i>0)
fprintf(fout, "\n");
} else {
fprintf(fout, " ");
}
fprintf(fout, "%d", s[i]);
}
fprintf(fout, "\n");
}
fclose(fout);
return 0;
}
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