#include <bits/stdc++.h>
#define ll long long

using namespace std;
ll pw[19];
ll dp[20][20][2];

void solve() {
    ll x;int k;
    cin >> x;
    cin >> k;
    vector<int>num(40, 0);
    // cout << x << endl;
    for (int i = 1; i <= 19; i ++ ) num[i] = (x / pw[i]) % 10;
    // for (auto &it : num_base) cout << it << ' ';cout << endl;
    if (k == 0) {
        for (int j = 1; j <= 19; ++j) {
            if (num[j] != 9) {
                cout << 1;
                for (int i = 1; i < j; ++i) cout << 0;cout << endl;
                return;
            }
        }
    }
    for (int i = 0; i <= 19; ++i) {
        for (int k = 0; k <= 19; ++k) {
            dp[i][k][0] = dp[i][k][1] = 2e18;
        }
    }
    dp[0][0][0] = 0;
    // dp[1][0][1] = (num[0] > 0 ? 10 - num[0] : 2e18);
    for (int i = 1; i <= 18; ++i) {
        dp[i][0][0]= 0;
        for (int k = 1; k <= i; ++k) {
            if (num[i] != 0) dp[i][k][1] = min(dp[i - 1][k - 1][0] + (10 - num[i]) * pw[i], dp[i - 1][k - 1][1] + (10 - 1 - num[i]) * pw[i]);
            else dp[i][k][1] = dp[i - 1][k - 1][1] + (10 - 1 - num[i]) * pw[i];
            if(num[i] != 9) dp[i][k][0] = min(dp[i - 1][k][0], dp[i - 1][k][1]);
            else  dp[i][k][0] = dp[i - 1][k][0];
        }
    }
    if (dp[18][k][0] < 2e18) {
        cout << dp[18][k][0] << endl;
        return;
    }
    // cout << "NO: ";
    for (int j = k; j >= 0; --j) {
        if (dp[18][j][1] < 2e18) {
            for (int i = 0; i < k - j; ++i) cout << 9;
            cout << dp[18][j][1] << endl;
            return;
        }
    }
}

signed main() {
#ifdef DEBUG
    freopen("demo.in", "r", stdin);
    freopen("demo.out", "w", stdout);
#endif
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    int T;
    cin >> T;
    pw[1] = 1;
    for (int i = 2; i <= 19; i ++ ) {
        pw[i] = pw[i - 1] * 10;
        // cout << pw[i] << endl;
    }
    
    for (int _ = 1; _ <= T; _ ++) {
        solve();
    }
    return 0;
}