we have N element array.
And we have (M+1) integers, as numaration starts form 0 to M.
so, (M+1) integers will be checked in every element of the array.
as, there's N elements in the array, so, final result is N*(M+1).  :)
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#include <iostream>
using namespace std;

int main()
{
    int n, m;

    cin >> n >> m;

    cout << n * (m + 1) << '\n';

    return 0;
}
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