#include <stdio.h>
 
int main(void)
{
	int c = 0;
    int n = 0;
    char str[] = "30\0";
    int res = sscanf(str,"%d %n", &c, &n);
 
    printf("c = %d\n", c);
    printf("n = %d\n", n);
    printf("res = %d\n", res);
 
	return 0;
}