Beginner1007.c

#include <stdio.h>

int main() {

	int A, B, C, D, DIFERENCA;
	scanf("%d %d %d %d", &A, &B, &C, &D);

	DIFERENCA = (A * B) - (C * D);

	printf("DIFERENCA = %d", DIFERENCA);
	printf("\n");

	return 0;
}