#include <bits/stdc++.h>

#define x first
#define y second
#define el '\n'
#define debug(x) cerr << #x << ": " << x << endl
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int N = 3e5 + 10, INF = 0x3f3f3f3f, mod = 998244353;

vector<int> read() {
    vector<int> k;
    char c = getchar();
    while (c < '0' || c > '9') c = getchar();
    while (c >= '0' && c <= '9') {
        k.emplace_back(c - '0');
        c = getchar();
    }
    reverse(k.begin(), k.end());
    return k;
}

void print(vector<int> &a) {
    for (int i = a.size() - 1; i >= 0; --i) putchar('0' + a[i]);
    puts("");
}

int cmp(const vector<int> &a, const vector<int> &b) {
    if (a.size() > b.size()) return 1;
    if (a.size() < b.size()) return -1;
    for (int i = a.size() - 1; i >= 0; --i) {
        if (a[i] > b[i]) return 1;
        if (b[i] > a[i]) return -1;
    }
    return 0;
}

vector<int> mul(const vector<int> &a, ll k) {
    vector<int> res(a.size());
    ll t = 0;
    for (int i = 0; i < a.size(); ++i) {
        t += a[i] * k;
        res[i] = t % 10;
        t /= 10;
    }
    while (t) {
        res.emplace_back(t % 10);
        t /= 10;
    }
    return res;
}

vector<int> add(const vector<int> &a, ll k) {
    ll t = k;
    vector<int> res(a.size());
    for (int i = 0; i < a.size(); ++i) {
        t += a[i];
        res[i] = t % 10;
        t /= 10;
    }
    while (t) {
        res.emplace_back(t % 10);
        t /= 10;
    }
    return res;
}

void shrink(vector<int> &a) {
    while (a.size() > 1 && !a.back()) a.pop_back();
}

vector<int> del(const vector<int> &a, ll k) {
    ll t = -k;
    vector<int> res(a.size());
    for (int i = 0; i < a.size(); ++i) {
        t += a[i];
        res[i] = t % 10;
        t /= 10;
        if (res[i] < 0) res[i] += 10, --t;
    }
    assert(!t);
    // while (t) {
    //     res.emplace_back(t % 10);
    //     t /= 10;
    // }
    shrink(res);
    return res;
}

vector<int> div(const vector<int> &a, ll k) {
    vector<int> res(a.size());
    ll t = 0;
    for (int i = a.size() - 1; i >= 0; --i) {
        t += a[i];
        res[i] = t / k;
        t %= k;
        t *= 10;
    }
    shrink(res);
    return res;
}

void solve() {
    vector<int> n = read();
    ll m; scanf("%lld", &m);
    vector<int> ans = mul(div(n, m), m);
    ans = add(ans, m);
    n = add(n, 1);
    for (int i = 0; i < n.size(); ++i) {
        int t = m;
        int p = i, ok = 1;
        while (t) {
            if (p >= n.size() || n[p] != t % 10) {
                ok = 0;
                break;
            }
            t /= 10;
            ++p;
        }
        if (ok) return print(n);
    }
    ll pw = 1;
    int p = 0;
    vector<int> tt = n;
    while (pw <= m) {
        pw *= 10;
        if (p < tt.size()) tt[p++] = 0;
    }
    shrink(tt);
    ll mm = m;
    while (pw <= 1e12) {
        auto t = add(tt, mm);
        if (cmp(t, n) < 0) t = add(t, pw);
        if (cmp(t, ans) < 0) ans = move(t);
        if (p < tt.size()) tt[p++] = 0, shrink(tt);
        pw *= 10;
        mm *= 10;
    }
    ll sum = 0;
    ll mn = 0;
    tt = n;
    for (int i = 0; i < 20; ++i) tt.emplace_back(0);
    vector<ll> pow(18);
    pow[0] = 1;
    for (int i = 1; i <= 17; ++i) pow[i] = pow[i - 1] * 10;
    for (int i = 0; i < tt.size() - 20; ++i) {
        int t = m;
        int p = i, ok = 1;
        ll res = 0;
        while (t) {
            if (t % 10 != tt[p]) {
                if (p > 10) {
                    ok = 0;
                    break;
                }
                res += (t % 10 - tt[p]) * pow[p];
            }
            t /= 10;
            ++p;
        }
        if (res < 0) continue;
        mn = min(mn, res + sum);
        if (tt[i] && i > 10) break;
        sum += tt[i] * pow[i];
        tt[i] = 0;
        ++tt[i + 1];
        p = i + 1;
        while (tt[p] >= 10) ++tt[p + 1], tt[p] -= 10, ++p;
        if (!ok) break;
    }
    auto ans2 = add(n, mn);
    if (cmp(ans2, ans) < 0) ans = move(ans2);
    print(ans);
}

int main() {
    // ios::sync_with_stdio(0); cin.tie(0);
    int tcase = 1;
    cin >> tcase;
    while (tcase--) solve();
}