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

using namespace std;
ll pw[19];
void solve() {
    ll x;int k;
    cin >> x;
    cin >> k;
    vector<int>num_base(40, 0);
    // cout << x << endl;
    for (int i = 0; i <= 18; i ++ ) num_base[i] = (x / pw[i]) % 10;
    // for (auto &it : num_base) cout << it << ' ';cout << endl;
    if (k == 0) {
        for (int j = 0; j <= 19; ++j) {
            if (num_base[j] != 9) {
                cout << 1;
                for (int i = 0; i < j; ++i) cout << 0;cout << endl;
                return;
            }
        }
    }
    for (int i = 0; i <= 20; ++i) {
        int cnt = 0, pos = i;
        vector<int>ans(40);
        vector<int>num = num_base;  
        while (cnt < k) {
            if (num[pos] == 0) {
                pos++;continue;
            }
            ans[pos] = 10 - num[pos];
            num[pos + 1]++;
            cnt++;
            pos++;
        }
        // cout << "T" << i << " cnt-" << cnt << " : "; for (auto &it : ans) cout << it << ' ';cout << endl;
        if (num[pos] >= 10) continue;
        // cout << pos << " : ";
        int j = pos;
        while (j >= 0 && ans[j] == 0) j--;
        for (; j >= 0; --j) cout << ans[j];cout << 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[0] = 1;
    for (int i = 1; i <= 18; i ++ ) {
        pw[i] = pw[i - 1] * 10;
        // cout << pw[i] << endl;
    }
    
    for (int _ = 1; _ <= T; _ ++) {
        solve();
    }
    return 0;
}