int c;
int len = strlen(format);
int cnt = 0;
for (c = 0; c < (len - 1); c++)
if (format[c] == '%' && format[c + 1] == 's')
cnt++;
int c;
int len = strlen(format);
int cnt = 0;
for (c = 0; c < (len - 1); c++)
if (format[c] == '%' && format[c + 1] == 's')
cnt++;