#include <bits/stdc++.h>
using namespace std;
// #include <ext/pb_ds/priority_queue.hpp>
// #include <ext/pb_ds/assoc_container.hpp>
// using namespace __gnu_pbds;
#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
#define ordered_multiset tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update>
/* ordered_set notes:
    .order_of_key(k): Number of items strictly smaller than k
    .find_by_order(k): k-th element in a set
*/
#define X first
#define Y second
template <typename A, typename B> istream& operator >> (istream& o, pair<A, B> &a) {
    return o >> a.X >> a.Y;
}
template <typename A, typename B> ostream& operator << (ostream& o, pair<A, B> a) {
    return o << '(' << a.X << ", " << a.Y << ')';
}
#ifdef cychien
#define DE(...) do {\
	fprintf(stderr, "%s - %d : (%s) = ", __PRETTY_FUNCTION__, __LINE__, #__VA_ARGS__);\
    _DO(__VA_ARGS__);\
}while(0) 
template<typename I> void _DO(I&&x) {cerr << x << '\n';}
template<typename I, typename ...T> void _DO(I&&x,T&&...tail) {cerr << x << ", "; _DO(tail...);}
#define IOS
#define debug(v) {cerr << #v << " = ["; for(auto it = (v).begin(); it != (v).end(); it++){cerr << *it; if (next(it) != (v).end()) cerr << ", "; } cerr << "]\n";}
#else
#define DE(...)
#define debug(v)  
#define IOS ios_base::sync_with_stdio(0);cin.tie(0)
#endif
#define W(v) {for(auto it = (v).begin(); it != (v).end(); it++)cout << *it << " \n"[next(it) == (v).end()];}
#define pb emplace_back
#define mp make_pair
#define rsz resize
#define SZ(x) (ll)x.size()
#define AI(x) (x).begin(),(x).end()
#define SORT(x) sort(AI(x))
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
typedef long long int ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vll;
const int NF = 0x3f3f3f3f;
const ll INF = 0x3f3f3f3f3f3f3f3f;
const ll MOD = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int Rand(){
    return uniform_int_distribution<int>(1, 999999)(rng);
}
/*
#include <atcoder/all>
using namespace atcoder;
*/

/* LazySegtree

// Example for range linear transfromation & range sum
// Monoid Property: op(F(a), F(b)) == F(op(a, b))
// Declaration: lazy_segtree<S, op, e, F, mapping, composition, id> seg(n);

struct S { // Node
    mint sum;
    int len;
};
S op(S x, S y){ // pull
    return S{x.sum + y.sum, x.len + y.len};
}
S e(){ // e s.t. op(x, e) == x
    return S{0, 1};
}
 
struct F {
    mint a, b;
};
S mapping(F t, S x){ // push
    return S{t.a * x.sum + t.b * x.len, x.len};
}
F composition(F f, F g){ // f o g
    return F{f.a * g.a, f.a * g.b + f.b};
}
F id() { // id s.t. composition(F, id) == F
    return F{1, 0};
}

*/
const __int128_t C = 1e36;
__int128_t pow10[37];
/*
int ds(unsigned long long x){
    string s = to_string(x);
    int ans = 0;
    for (auto c : s) ans += c - '0';
    return ans;
}
int carries(unsigned long long x, unsigned long long y){
    return (-ds(x + y) + ds(x) + ds(y)) / 9;
}
unsigned long long brute(string s, int k){
    unsigned long long x = stoll(s);

    for (unsigned long long i = 1; ; i++){
        if (carries(x, i) == k){
            return i;
        }
    }
}
*/
void display(__int128_t x){
    if (x){
        display(x / 10);
        cout << (int)(x % 10);
    }
}
void solve(){
    string s; int k; cin >> s >> k;
    reverse(AI(s));
    s += '0';
    int n = SZ(s);
    if (k == 0){
        for (int i = 0; i < n; ++i){
            if (s[i] != '9'){
                cout << 1;
                for (int j = i - 1; j >= 0; --j){
                    cout << 0;
                }
                cout << '\n';
                return;
            }
        }
    }
    vector<vector<vector<__int128_t>>> dp(n, vector<vector<__int128_t>>(k + 1, vector<__int128>(2, C)));

    vector<int> delta(n);
    for (int x = n - 1; x >= 0; --x){
        int ptr = x + 1;
        while (s[ptr] == '9') ++ptr;
        delta[x] = ptr - x;
    }
    for (int x = n - 1; x >= 0; --x){
        for (int y = 0; y <= k; y++){
            for (int o = 0; o <= 1; o++){
                if (y == 0){
                    dp[x][y][o] = 0;
                }
                else if (x == n - 1){
                    if (o == 1){
                        __int128_t ret = 10 - o - (s[x] - '0');
                        for (int z = 0; z < y - 1; z++) ret = ret * 10 + 9;
                        chmin(dp[x][y][o], ret);
                    }
                }
                else {
                    chmin(dp[x][y][o], dp[x + 1][y][0] * 10);
                    if (10 - o - (s[x] - '0') < 10 && delta[x] <= y){
                        chmin(dp[x][y][o], 10 - o - (s[x] - '0') + dp[x + delta[x]][y - delta[x]][1] * pow10[delta[x]]);
                    }
                }
            }
        }
    }

    __int128_t ans = dp[0][k][0];
    display(ans);
    cout << '\n';
}
int main() {
    IOS;
    pow10[0] = 1;
    for (int i = 1; i < 37; i++) pow10[i] = pow10[i - 1] * 10;
    /*
    for (int times = 0; times < 100000; times++){
        int x = Rand();
        for (int k = 1; k <= 5; k++){
            solve(x, k);
        }
    }
    exit(0);
    */
    int T; cin >> T;
    while (T--) solve();
    return 0;
}