If you are new to programming and do not know what to start with, first try Problem A “Welcome to Atcoder” in “practicecontest”(https://atcoder.jp/contests/practice/). There you can find a sample code for each language.

In this problem, you are asked to input \(a, b, c, d\) and output \(a \times d - b \times c\).

Sample Code (C++)

#include <iostream>
using namespace std;
int main(){
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    cout << a * d - b * c << endl;
}

Sample Code (Python)

a, b = map(int, input().split())
c, d = map(int, input().split())
print(a * d - b * c)