#include<bits/stdc++.h>
using namespace std;
#define endl "\n"
#define debug(x) cout<<#x<<": "<<x<<endl
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
using ll=long long;
using ull=unsigned long long;
#define int long long
using i128 = __int128;

void print(__int128 x)
{
    if (x < 0)
    {
        cout<<('-');
        x = -x;
    }
    if (x > 9)
        print(x / 10);
    char ch=(x % 10 + '0');
    cout<<ch;
}
__int128 c10[40];
__int128 nu[10];

int x,k;
string s;
int n;
__int128 res,now;
string cur;
int cnt;
int dp[40];
int vis[40][40][2];
void dfs(int i,int carry){
        if(cnt>k||i>36)
            return;
        if(res<now&&res!=0)
            return;
        // if(vis[i][cnt][carry])
        //     return;
        vis[i][cnt][carry]=1;
        if((!carry&&cnt==k)||(carry&&cnt+dp[i]==k)){
            if(res==0)
                res=now;
            else
                res=min(res,now);
            return;
        }
        if(carry&&s[i]=='9'){
            cur+='0';
            cnt++;
            dfs(i+1,1);
            cnt--;
            cur.pop_back();
            return;
        }
        //jin
        if(carry){
            int ad=10-(s[i]-'0'+1);
            cur+='0'+ad;            
            cnt++;
            now+=nu[ad]*c10[i];
            
            dfs(i+1,1);
            now-=nu[ad]*c10[i];
            cnt--;
            cur.pop_back();
        }
        else{
            int ad=10-(s[i]-'0');
            if(ad!=10){
                cur+='0'+ad;                
                cnt++;
                now+=nu[ad]*c10[i];
                dfs(i+1,1);
                now-=nu[ad]*c10[i];
                cnt--;
                cur.pop_back();
            }
        }
        
        // //no jin
        
        cur+='0';
        dfs(i+1,0);
        cur.pop_back();
        
    };
void solve(){
    cin>>x>>k;
    s=to_string(x);
    n=s.size();
    if(k==0){
        string cur;
        for(int i=s.size()-1;i>=0;i--){
            if(s[i]!='9'){
                cur+='1';
                reverse(cur.begin(),cur.end());
                cout<<cur<<endl;
                return;
            }
            else{
                cur+='0';
            }
        }
        cur+='1';
        reverse(cur.begin(),cur.end());
        cout<<cur<<endl;
        return;
    }
    res=0;
    now=0;
    reverse(s.begin(),s.end());
    for(int i=0;i<40;i++)
        s+='0';
    cur="";
    cnt=0;
    memset(dp,0,sizeof dp);
    for(int i=0;i<40;i++){
        int cc=0;
        for(int j=i;j<40;j++){
            if(s[j]=='9')
                cc++;
            else
                break;
        }
        dp[i]=cc;
    }
    now=0;
    memset(vis,0,sizeof vis);
    dfs(0,0);
    print(res);
    cout<<endl;
}
signed main(){
    ios::sync_with_stdio(0);
    cout.tie(0);
    cin.tie(0);
    c10[0]=1;
    __int128 ten=10;
    for(int i=1;i<40;i++){
        c10[i]=c10[i-1]*ten;
    }
    for(int i=0;i<10;i++)
        nu[i]=i;
    int t;
    cin>>t;
    while(t--){
        solve();
    }
}