#include <bits/stdc++.h>
using namespace std;
__int128 wei[39];
__int128 dp0[40][40];//该位不接受低位进位的情况下，dp[i][j]前i位进了j个位最小值是多少，若不存在则为0
__int128 dp1[40][40];//该位接受低位进位的情况下，dp[i][j]前i位进了j个位最小值是多少

void print(__int128 x) {
	stack<int>st;
	while (x > 0) {

		st.push(x % 10);
		x /= 10;
	}
	while (st.size()) {
		cout << st.top();
		st.pop();
	}
	cout << endl;
}

void solve() {
	string str, tem;
	int K, lim;
	cin >> str >> K;

	for (int i = 1; i < K; i ++) {
		tem += '0';
	}
	str = tem + str;
	str = '?' + str;
	int siz = str.size() - 1;

	for (int i = 1; i <= siz; i ++) {
		for (int j = 0; j <= K; j ++) {
			dp0[i][j] = -1;
			dp1[i][j] = -1;
		}
	}
	dp0[1][0] = 0;

	if (str[1] == '0') {
		dp0[1][1] = -1;

	} else {
		dp0[1][1] = wei[siz];
		dp0[1][1] *= 10 - str[1] + '0';
	}

	if (str[1] == '9') {
		dp1[1][0] = -1;
		dp1[1][1] = 0;

	} else {
		dp1[1][0] = 0;
		dp1[1][1] = wei[siz];
		dp1[1][1] *= 9 - str[1] + '0';
	}

	for (int i = 2; i <= siz; i ++) {
		for (int j = 0; j <= i and j <= K; j ++) {
			//dp0[i][j] = ?;
			if (str[i] == '0') {
				dp0[i][j] = dp0[i - 1][j];
			} else {
				if (dp0[i - 1][j] == -1) {
					if (j == 0 or dp1[i - 1][j - 1] == -1) {
						dp0[i][j] = -1;
					} else {
						dp0[i][j] = dp1[i - 1][j - 1] + wei[siz - i + 1] * (10 - str[i] + '0');
					}
				} else {
					if (j == 0 or dp1[i - 1][j - 1] == -1) {
						dp0[i][j] = dp0[i - 1][j];
					} else {
						dp0[i][j] = min(dp0[i - 1][j], dp1[i - 1][j - 1] + wei[siz - i + 1] * (10 - str[i] + '0'));
					}
				}
			}
			//dp1[i][j] = ?;
			if (str[i] == '9') {
				if (j == 0) {
					dp1[i][j] = -1;
				} else {
					dp1[i][j] = dp1[i - 1][j - 1];
				}
			} else {
				if (dp0[i - 1][j] == -1) {
					if (j == 0 or dp1[i - 1][j - 1] == -1) {
						dp1[i][j] = -1;
					} else {
						dp1[i][j] = dp1[i - 1][j - 1] + wei[siz - i + 1] * (9 - str[i] + '0');
					}
				} else {
					if (j == 0 or dp1[i - 1][j - 1] == -1) {
						dp1[i][j] = dp0[i - 1][j];
					} else {
						dp1[i][j] = min(dp0[i - 1][j], dp1[i - 1][j - 1] + wei[siz - i + 1] * (9 - str[i] + '0'));
					}
				}
			}
		}
	}
	if (dp0[siz][K] == 0) {
		dp0[siz][K] = 1;
	}
	print(dp0[siz][K]);
}

int main() {
//	ios::sync_with_stdio(false);
//	cin.tie(0);
//	cout.tie(0);
	int T;
	cin >> T;
	wei[1] = 1;

	for (int i = 2; i <= 38; i ++) {
		wei[i] = wei[i - 1] * 10;
	}

	while (T --) {
		solve();
	}
}