#include <bits/stdc++.h>
#define int long long
using namespace std;
const int N = 25;
int t, K, L;
int a10[N];
int s, k;
int a[N];
int dp[N][N];
signed main()
{
	a10[0] = 1;
	for (int i = 1; i < 18; i++)
		a10[i] = a10[i - 1] * 10;
	cin >> t;
	while (t--) {  //补充一个特判
		cin >> s >> k;
		if (k == 0) {
			string ss;
			while (s >= 1) {
				int res = s % 10;
				s = s / 10;
				if (res == 9)
					ss.push_back('0');
				else {
					ss.push_back('1');
					break;
				}
			}
			for (int i = ss.size() - 1; i >= 0; i--) {
				cout << ss[i];
			}
			cout << endl;
			continue;
		}
		L = 0;
		for (int i = 0; i < 18; i++) {
			a[i] = s % 10;
			if (a[i])
				L = i;
			s /= 10;
		}
		if (a[0] == 9) {
			int tt = 0;
			while (a[tt] == 9)
				tt++;
			if (tt == k) {
				cout << 1 << endl;
				continue;
			}
		}
		L = max(L, k - 1);
		for (int i = 0; i <= 18; i++)
			for (int j = 1; j <= 18; j++)
				dp[i][j] = -1;
		// dp[0][0]=0;
		if (a[0])
			dp[0][1] = 10 - a[0];
		for (int i = 1; i <= L; i++) {
			if (a[i])
				dp[i][1] = a10[i] * (10 - a[i]);
			for (int j = 2; j <= i + 1; j++) {
				if (a[i] > 0) {
					for (int j1 = 0; j1 <= i - 2; j1++) {
						if ((a[j1] + a[j1 + 1] != 18) && ~dp[j1][j - 1])
							dp[i][j] = dp[j1][j - 1];
					}
				}
				if (~dp[i - 1][j - 1])
					dp[i][j] = dp[i - 1][j - 1] + a10[i] * (9 - a[i]);
			}
		}
		int ans = 0;
		for (int i = 0; i < 18; i++) {
			if (~dp[i][k] && a[i] + a[i + 1] != 18) {
				if (dp[i][k] == 0)
					dp[i][k]++;
				cout << dp[i][k] << endl;
				ans = 1;
				break;
			}
		}
		if (!ans)
			cout << -1 << endl;
	}
	return 0;
}