C :

#include <stdio.h>
 int main()
 { 
   int a,b,c,d;
   scanf("%d%d%d%d",&a,&b,&c,&d);
   printf("DIFERENCA = %d",(a*b-c*d));
   return 0;
 }

C++ :

#include<iostream>

using namespace std;

int main()
{
    int A,B,C,D;
    
    cin>>A>>B>>C>>D;

    cout<<"DIFERENCA = "<<A*B-C*D<<endl;
    
    return 0;
}

Java :

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        int up =10000;
        int low = -10000;
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();
        int D = scanner.nextInt();
        if (A <= up && A>=low && B <= up && B>=low && C<=up && C>=low && D<=up && D>=low) {
          int DIFERENCA = (A*B-C*D);
            System.out.println("DIFERENCA = "+DIFERENCA);
        }
    }
}