#include <bits/stdc++.h>
#define int long long
#define ll __int128
#define ull unsigned long long
using namespace std;
ll f[37][20][2];
int a[37];
ll base[37];
void write(ll x){
    if (x>9){
        write(x/10);
    }
    putchar(x%10+'0');
}
void paralysis(){
    int x,k;
    cin>>x>>k;
    int len=0;
    while (x){
        a[++len]=x%10;
        x/=10;
    }
    if (a[1]==9&&k==0){
        cout<<"-1\n";
        return;
    }

    for (int i=0;i<=36;i++){
        for (int j=0;j<=k;j++){
            for (int l=0;l<2;l++){
                f[i][j][l]=-1;
            }
        }
    }

    f[0][0][0]=0;
    for (int i=1;i<=36;i++){
        for (int j=0;j<=k;j++){
            if (f[i-1][j][1]!=-1){
                for (int x=0;x<=9;x++){
                    int now=(x+1+a[i]);
                    if (now>=10&&j+1<=k){
                        if (f[i][j+1][1]!=-1){
                            f[i][j+1][1]=min(f[i][j+1][1],f[i-1][j][1]+base[i-1]*x);
                        }else{
                            f[i][j+1][1]=f[i-1][j][1]+base[i-1]*x;
                        }
                    }
                    if (now<10){
                        if (f[i][j][0]!=-1){
                            f[i][j][0]=min(f[i][j][0],f[i-1][j][1]+base[i-1]*x);
                        }else{
                            f[i][j][0]=f[i-1][j][1]+base[i-1]*x;
                        }
                    }
                }
            }
            if (f[i-1][j][0]!=-1){
                // cout<<i-1<<" "<<j<<"\n";
                for (int x=0;x<=9;x++){
                    int now=(x+a[i]);
                    if (now>=10&&j+1<=k){
                        if (f[i][j+1][1]!=-1){
                            f[i][j+1][1]=min(f[i][j+1][1],f[i-1][j][0]+base[i-1]*x);
                        }else{
                            f[i][j+1][1]=f[i-1][j][0]+base[i-1]*x;
                        }
                    }
                    if (now<10){
                        // cout<<x<<"\n";
                        if (f[i][j][0]!=-1){
                            f[i][j][0]=min(f[i][j][0],f[i-1][j][0]+base[i-1]*x);
                        }else{
                            f[i][j][0]=f[i-1][j][0]+base[i-1]*x;
                        }
                    }
                }
            }
        }
    }

    ll ans=0;
    if (f[36][k][0]!=-1&&f[36][k][1]!=-1){
        ans=min(f[36][k][0],f[36][k][1]);
    }else if (f[36][k][0]!=-1){
        ans=f[36][k][0];
    }else if (f[36][k][1]!=-1){
        ans=f[36][k][1];
    }else{
        cout<<"-1\n";
        return;
    }

    if (ans==0){
        ans=1;
    }
    write(ans);
    puts("");
}
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    base[0]=1;
    for (int i=1;i<=36;i++){
        base[i]=base[i-1]*10;
    }
    
    int T=1;
    cin>>T;
    while (T--){
        paralysis();
    }
    return 0;
}