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#include "str.h"
/* str_start returns 1 if the b is a prefix of a, 0 otherwise */
int str_start(const char* a, const char* b) {
#if 1
size_t i;
for (i=0; ; ++i) {
if (!b[i]) return 1;
if (a[i]!=b[i]) break;
}
return 0;
#else
register const char* s=a;
register const char* t=b;
for (;;) {
if (!*t) return 1;
if (*s!=*t) break;
++s; ++t;
if (!*t) return 1;
if (*s!=*t) break;
++s; ++t;
if (!*t) return 1;
if (*s!=*t) break;
++s; ++t;
if (!*t) return 1;
if (*s!=*t) break;
++s; ++t;
}
return 0;
#endif
}
#ifdef UNITTEST
#include <assert.h>
int main() {
assert(str_start("fnord","no")==0);
assert(str_start("fnord","fno")==1);
assert(str_start("fnord","fnord")==1);
assert(str_start("fnord","fnord1")==0);
return 0;
}
#endif
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