#include<string>
#include <iostream>
using namespace std;


int main() {

	int t;
	cin >> t;
	int x, y,num=0;
	while (t--) {

		cin >> x >> y;
		num = x;
		while (num % y != 0)
		{
			num = num + 1;
			
		}
		cout << num << endl;
	}





}