#include <string.h>
-char *strncat(char *d, const char *s, size_t n)
+char *strncat(char *restrict d, const char *restrict s, size_t n)
{
char *a = d;
d += strlen(d);
- while (n && (*d++ = *s++)) n--;
+ while (n && *s) n--, *d++ = *s++;
*d++ = 0;
return a;
}