#include <iostream>
#include <math.h>
using namespace std;
#define ll long long int
int main() {
ll t;
ll first, second;
cin >> t;
while (t--) {
cin >> first >> second;
ll k = first;
if (first <= second)
cout << second << endl;
else if (k > second) {
ll part = (k / second) + 1;
cout << second * part << endl;
}
}
}