#include<bits/stdc++.h>
using namespace std;

#define ll __int128

int t,k,len;
int a[50];
string s;
ll dp[50][50];
ll minn[50];
ll ans;

void write(__int128 x){
    if(x > 9)
        write(x / 10);
    putchar(x % 10 + '0');
}
bool vis[50][50];
bool vis2[50];
bool vis_ans;
ll _pow[50];

int main()
{
    _pow[0]=1;
    for(int i=1;i<=40;++i)
    {
        _pow[i] = _pow[i-1]*10;
    }
    cin>>t;
    while(t--)
    {
        string str;
        cin>>str>>k;
        s='0'+str;
        len=str.length();
        
        if(k==0)
        {
            int cnt=len;
            while(cnt>0 && s[cnt]=='9')
            {
                cnt--;
            }
            cout<<1;
            for(int i=cnt+1;i<=len;++i) cout<<0;
            cout<<endl;
            continue;
        }

        memset(vis,0,sizeof(vis));
        memset(vis2,0,sizeof(vis2));
        vis_ans=0;
        for(int i=1;i<=40;++i) a[i]=0;
        for(int i=len;i>=1;--i)
        {
            a[len-i+1]=s[i]-'0';
        }
        /*for(int i=1;i<=40;++i)
        {
            for(int j=1;j<=40;++j)
            {
                dp[i][j]=maxn;
            }
            minn[i]=maxn;
        }*/
        for(int i=1;i<=40;++i)
        {
            if(a[i]!=0) 
            {
                dp[i][1]=(10-a[i])*_pow[i-1];
                vis[i][1]=1;
            }  
        }
        for(int i=2;i<=40;++i)
        {   
            for(int j=2;j<=k;++j)
            {
                if(vis[i-1][j-1] == 1)
                {
                    if(vis[i][j])
                        dp[i][j]=min(dp[i][j], dp[i-1][j-1]+(10-1-a[i])*_pow[i-1]);
                    else
                    {
                        dp[i][j]=dp[i-1][j-1]+(10-1-a[i])*_pow[i-1];
                        vis[i][j]=1;
                    }
                }
                if(a[i]!=0 && vis2[j-1] == 1)
                {
                    if(vis[i][j])
                        dp[i][j]=min(dp[i][j], minn[j-1]+(10-a[i])*_pow[i-1]);
                    else
                    {
                        dp[i][j]=minn[j-1]+(10-a[i])*_pow[i-1];
                        vis[i][j]=1;
                    }
                }
            }
            for(int j=1;j<=k;++j)
            {
                if(vis[i-1][j]) 
                {
                    if(vis2[j])
                    {
                        minn[j]=min(minn[j], dp[i-1][j]);
                    }
                    else
                    {
                        minn[j]=dp[i-1][j];
                        vis2[j]=1;
                    }
                }
            }
        }
        for(int i=k;i<=36;++i)
        {
            if(a[i+1]!=9 && vis[i][k]==1)
            {
                if(vis_ans==0)
                {
                    ans=dp[i][k];
                    vis_ans=1;
                }
                else
                {
                    ans=min(ans, dp[i][k]);
                }
            }
        }
        write(ans);
        cout<<endl;
    }
    // system("pause");
    return 0;
}
/*
1
100000000000000000 18

*/