#include<vector>
#include<set>
#include<map>
#include<queue>
#include<string>
#include<algorithm>
#include<iostream>
#include<bitset>
#include<functional>
#include<chrono>
#include<numeric>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cassert>
#include<cmath>
#include<iomanip>
#include<random>
#include<ctime>
#include<complex>
#include<type_traits>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
typedef long long LL;
typedef double D;
#define all(v) (v).begin(), (v).end()
mt19937 gene(chrono::system_clock::now().time_since_epoch().count());
typedef complex<double> Complex;
typedef pair<int, int> pii;
#define fi first
#define se second
#define ins insert
#define pb push_back
inline char GET_CHAR(){
    const int maxn = 131072;
    static char buf[maxn],*p1=buf,*p2=buf;
    return p1==p2&&(p2=(p1=buf)+fread(buf,1,maxn,stdin),p1==p2)?EOF:*p1++;
}
inline int getInt() {
    int res(0);
    char c = getchar();
    while(c < '0') c = getchar();
    while(c >= '0') {
        res = res * 10 + (c - '0');
        c = getchar();
    }
    return res;
}
inline LL fastpo(LL x, LL n, LL mod) {
    LL res(1);
    while(n) {
        if(n & 1) {
            res = res * (LL)x % mod;
        }
        x = x * (LL) x % mod;
        n /= 2;
    }
    return res;
}
template<LL mod> struct Num {
    LL a;
    Num operator + (const Num & b) { return Num{(a + b.a) % mod}; }
    Num operator - (const Num & b) { return Num{(a - b.a + mod) % mod}; }
    Num operator * (const Num & b) { return Num{a * b.a % mod}; }
    Num operator / (const Num & b) { return Num{a * fastpo(b.a, mod - 2, mod) % mod}; }
    void operator += (const Num & b) {if((a += b.a) >= mod) a -= mod;}
    void operator -= (const Num & b) {if((a -= b.a) < 0) a += mod;}
    void operator *= (const Num & b) { a = a * b.a % mod; }
    void operator /= (const Num & b) { a = a * fastpo(b.a, mod - 2, mod) % mod; }
    void operator = (const Num & b) { a = b.a; }
    void operator = (const LL & b) { a = b; }
};
template<LL mod> ostream & operator << (ostream & os, const Num<mod> & a) {
    os << a.a;
    return os;
}
LL gcd(LL a, LL b) { return b ? gcd(b, a % b) : a; }
inline string itoa(LL x, int width = 0) {
    string res;
    if(x == 0) res.push_back('0');
    while(x) {
        res.push_back('0' + x % 10);
        x /= 10;
    }
    while((int)res.size() < width) res.push_back('0');
    reverse(res.begin(), res.end());
    return res;
}
const int _B = 131072;
char buf[_B];
int _bl = 0;
inline void flush() {
    fwrite(buf, 1, _bl, stdout);
    _bl = 0;
}
__inline void _putchar(char c) {
    if(_bl == _B) flush();
    buf[_bl++] = c;
}
inline void print(LL x, char c) {
    static char tmp[20];
    int l = 0;
    if(!x) tmp[l++] = '0';
    else {
        while(x) {
            tmp[l++] = x % 10 + '0';
            x /= 10;
        }
    }
    for(int i = l - 1; i >= 0; i--) _putchar(tmp[i]);
    _putchar(c);
}
typedef double C;
struct P {
    C x, y;
    void scan() {
        double _x, _y;
        scanf("%lf%lf", &_x, &_y);
        x = _x; y = _y;
    }
    void print() {
        cout << '(' << x << ' ' << y << ')' << endl;
    }
    P operator + (const P & b) const { return P{x + b.x, y + b.y}; }
    P operator - (const P & b) const { return P{x - b.x, y - b.y}; }
    C operator * (const P & b) const { return x * b.y - y * b.x; }
    C operator % (const P & b) const { return x * b.x + y * b.y; }
};
P operator * (const C & x, const P & b) { return P{x * b.x, x * b.y}; }
const int N = 1000133;
const int LOG = 20;
const int mod = 1e9 + 7;
const int inf = 1e9 + 7;
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
int rela[N];
int getr(int x) {
    int p = x;
    while(rela[p] != p) p = rela[p];
    int p1 = p; p = x;
    while(rela[p] != p) {
        int p2 = rela[p];
        rela[p] = p1;
        p = p2;
    }
    return p1;
}

char st[N];
int n[N];
LL toi(int * st, int * ed) {
    // printf("%p %p\n", st, ed);
    LL res = 0;
    for (int * p = ed - 1; ; p--) {
        res = res * 10 + (*p);
        if (p == st) {
            break;
        }
    }
    return res;
}
void solve() {
    int m;
    scanf("%s", st);
    scanf("%d", &m);
    // printf("!!\n");
    int len = strlen(st);
    LL rem = 0;
    
    // printf("!!\n");
    for (int i = 0; i < len; i++) {
        n[i] = st[i] - '0';
    }
    reverse(n, n + len);
    for (int i = len - 1; i >= 0; i--) {
        rem = (rem * 10 + n[i]) % m;
    }
    
    // printf("!!\n");
    int mlen = 0;
    int x = m;
    LL d = 1;
    LL pw = 1;
    
    // printf("!!\n");
    while (x) {
        // xm[mlen++] = x % 10;
        mlen++;
        d *= 10;
        x /= 10;
    }
    for (int i = 0; i <= mlen + 10; i++) {
        n[len++] = 0;
    }
    
    LL mn = inf;
    mn = rem == 0 ? m : m - rem;
    LL sat = 1;
    // printf("??\n");
    for (int i = 0; i + mlen <= len; i++) {
        // printf("i = %d\n", i);
        LL frm = toi(n + i, n + i + mlen);
        LL to = m;
        // printf("%d %lld %lld\n", i, frm, to);
        // printf("i = %d\n", i);
        if (frm == to) {
            mn = 0;
            break;
        }
        LL delta;
        if (frm < to) {
            delta = (to - frm - 1) * pw + sat;
        } else {
            delta = (to + d - frm - 1) * pw + sat;
        }
        if (delta < mn) {
            mn = delta;
        }
        sat += (9 - n[i]) * pw;
        if (sat > inf) {
            sat = inf;
        }
        pw = pw * 10;
        if (pw > inf) {
            pw = inf;
        }
    }
    for (int i = 0; i < len; i++) {
        mn += n[i];
        n[i] = mn % 10;
        mn /= 10;
    }
    while (n[len - 1] == 0) {
        len--;
    }
    for (int i = len - 1; i >= 0; i--) {
        printf("%d", n[i]);
    }
    printf("\n");
}
int main() {
    int t;
    scanf("%d", &t);
    for (int qq = 1; qq <= t; qq++) {
        solve();
    }
}