#include <stdio.h>

int mul(int, int);

int main(int argn, char* argv[])
{
    int a, b, p;
    if( argn == 3 && sscanf(argv[1], "%i", &a) && sscanf(argv[2], "%i", &b) ){
	p = mul(a, b);
	if( p != (a * b) ){
	    fprintf(stderr, "incorrect result: %d != %d * %d\n", p, a, b);
	    return 1;
	}
    }
    else if( argn == 2 && argv[1][0] == '-' && argv[1][1] == 'a' &&
	     argv[1][2] == '\0' )
	for(a = -256; a < 256; ++a){
	    for(b = -256; b < 256; ++b){
		p = mul(a, b);
		/* printf("%d * %d = %d\n", a, b, p); */
		if( p != (a * b) )
		    fprintf(stderr, "incorrect result: %d != %d * %d\n", p, a, b);
	    }
	}
    else fprintf(stderr, "bad arguments\n");
    return 0;
}