#include <bits/stdc++.h>
using namespace std;
using i64 = unsigned long long;

constexpr int N = 20;
constexpr i64 inf = 1.6e19;

int L[N], a[N], k;
i64 f[N][N][N];

inline void cmin(i64 &x, i64 y) {if(x > y) x = y;}

void solve() {
	i64 d; cin >> d >> k;
	int zeros = 0;
	while(d % 10 == 0) {
		d /= 10;
		zeros++;
	}
	if(k == 0) {
		while(d) {
			if(d % 10 == 9) {
				zeros++;
			} else {
				break;
			}
			d /= 10;
		}
		cout << "1" << string(zeros, '0') << "\n";
		return;
	}
	int t = -1;
	while(d) {
		L[++t] = d % 10;
		d /= 10;
	}
	
	memset(f, 0x3f, sizeof f);
	f[19][0][0] = 0;
	for(int i = 18; i >= 0; i--) {
		for(int x = 0; x <= k; x++) {
			for(int y = 0; y <= 18 - i; y++) {
				// f[i + 1][x][y] -> ?
				// case1: 进位
				if(x + y + 1 <= k && L[i] != 0) {
					cmin(f[i][x + y + 1][0], f[i + 1][x][y] * 10 + 10 - L[i]);
				}
				// case2: 产生 9
				cmin(f[i][x][y + 1], f[i + 1][x][y] * 10 + 9 - L[i]);
				// case3: 不产生 9，不进位
				if(L[i] != 9) {
					cmin(f[i][x][0], f[i + 1][x][y] * 10);
				}
			}
		}
	}
	i64 ans = inf;
	for(int i = 0; i <= 18; i++) {
		cmin(ans, f[0][k][i]);
	}
	cout << ans;
	cout << string(zeros, '0') << "\n";
}

int main() {
	ios::sync_with_stdio(false); 
	cin.tie(nullptr); cout.tie(nullptr);
	
	int T; cin >> T;
	while(T--) {
		solve();
	}
}
/*
Author: chroneZ
Start thinking at 
Start coding at 
Finish debugging at 
*/