No such file or directory

I tried to run a code in c ++ and it returned the following message: "g ++: error: / mnt / c / Users / valer / Documents / GitHub / Exercises / (1000) Simple-Equation.cpp: No such file or directory". Idk what to do.
`#include

using namespace std;

int main(){
int A, B, C, D, res;
cin >> A, B, C, D;
res = (A*B-C*D)
cout << res;
}
`
I'm using the Atom IDE with the Script Package (https://atom.io/packages/script) and the message appears every time I try to run a code in C ++