#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];
void solve(){
	int x,k;
	cin>>x>>k;
	string s=to_string(x);
	int 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;
	}
	__int128 res=0;
	reverse(s.begin(),s.end());
	for(int i=0;i<40;i++)
		s+='0';
	string cur;
	int cnt=0;
	vector<int> dp(40);
	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;
	}
	__int128 now=0;
	vector<vector<vector<int>>> vis(40,vector<vector<int>>(40,vector<int>(2)));
	auto dfs=[&](auto self,int i,int carry)->void{
		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++;
			self(self,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];
			
			self(self,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];
				self(self,i+1,1);
				now-=nu[ad]*c10[i];
				cnt--;
				cur.pop_back();
			}
		}
		
		// //no jin
		
		cur+='0';
		self(self,i+1,0);
		cur.pop_back();
		
	};
	dfs(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();
	}
}