#include <stdio.h>
int main(){
int A, B, C, D, diferenca;
scanf("%d\n%d\n%d\n%d", &A, &B, &C, &D);
diferenca = A * B - C * D;
printf("DIFERENCA = %d\n", diferenca);
return 0;
}
#include <iostream>
using namespace std;
int main(){
int A, B, C, D, diferenca;
cin >> A >> B >> C >> D;
diferenca = A * B - C * D;
cout << "DIFERENCA = " << diferenca << endl;
return 0;
}
let input = require("fs").readFileSync("/dev/stdin", "utf8");
let lines = input.split("\n");
let A = parseInt(lines.shift());
let B = parseInt(lines.shift());
let C = parseInt(lines.shift());
let D = parseInt(lines.shift());
let diferenca = A * B - C * D;
console.log(`DIFERENCA = ${diferenca}`);
A = int(input())
B = int(input())
C = int(input())
D = int(input())
diferenca = A * B - C * D
print(f"DIFERENCA = {diferenca}")