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


int main() {

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

		cin >> x >> y;
		if (x % y == 0)
			cout << x;
		else
		{
			cout << (((x / y) + 1) * y)<<endl;
		}
	
	
	}





}