Python:

a, b = map(int,input().split())
if b%a == 0:
    print("%d" % (a*b))
else:
    print("%d" % (a*(b-1)))

参考答案：

#include<iostream>

using namespace std;

int main()
{
    int a, b;

    cin >> a >> b;
    if (b % a == 0) cout << a * b << endl;
    else cout << a * (b - 1) << endl;

    return 0;
}