#include<bits/stdc++.h>
using namespace std;
#define int long long
int dp[40][40][2];
int qun[30];
void solve()
{
	int n,k;
	cin>>n>>k;
	memset(dp,0x3f,sizeof(dp));
	int tot = 0;
	
    while(n%10==0&&n!=0)
    {
    	tot++;
    	n/=10;
    }
    qun[0]= 1;
    for(int i=1;i<19;i++)
    qun[i] = qun[i-1]*10;
	vector<int> res(30);
	int cnt = 0;
	dp[0][0][0] = 0;
	while(n)
    {
        int x=n%10;
        n/=10;
        res[cnt++]=x;
    }
    if(k==0)
    {
        int s=1;
        for(int i=1;i<=19;i++)
        {
            if(res[i]!=9)
            {
                cout<<s;
                while(tot--)
                cout<<0;
                cout<<endl;
                
                return;
            }
            s*=10;
        }
    }
    for(int i=0;i<19;i++)
    {	for(int j=0;j<=k;j++)
    	{
    		int add =1 ;
    		while(res[i+add] == 9)
    			add++;
    		if(res[i] == 0)	
    		dp[i+add][j+add][1] = min(dp[i+add][j+add][1],dp[i][j][1]+(9-res[i])*qun[i]);
    		else
    		dp[i+add][j+add][1] = min({dp[i+add][j+add][1],dp[i][j][1]+(9-res[i])*qun[i],dp[i][j][0]+(10-res[i])*qun[i]});
    		dp[i+1][j][0] = min(dp[i][j][0],dp[i][j][1]);
    		
    	}
    }
    cout<<min(dp[18][k][0],dp[18][k][1]);
    while(tot--)
    cout<<0;
    cout<<endl;
    
}  
signed main (){
	std::ios::sync_with_stdio(false);  
	cin.tie(NULL); 
	cout.tie(NULL);
	int t;
	cin>>t;
	while(t--)
	solve();
}