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

typedef long long ll;
const __int128 inf=1e36;

ll v,k,tot;
__int128 a[40], dp[40][40][2], pw[40];

__int128 dfs(__int128 x,__int128 num,__int128 hav) {
	if(x==0) {
		if(num==k&&hav==0) return 0;
		return inf;
	}
	if(dp[x][num][hav]>=0) return dp[x][num][hav];
	__int128 res=inf;
	for(__int128 hav2=0;hav2<2;hav2++) {
		if(hav) {
			int c=10-a[x-1]-hav2;
			if(c>9) continue;
			res=min(res,dfs(x-1,num+hav,hav2)+c*pw[x-1]);
		}else {
			if(a[x-1]+hav2>9) continue; 
			res=min(res,dfs(x-1,num+hav,hav2));
		}
	}
	return dp[x][num][hav]=res;
}

void pt(__int128 x) {
	stack<int> q;
	while(x) q.push(x%10), x/=10;
	while(q.size()) cout<<q.top(), q.pop(); cout<<'\n';
	return ;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0), cout.tie(0);
	ll t; cin>>t;
	pw[0]=1;
	for(ll i=1;i<36;i++) pw[i]=pw[i-1]*10;
	while(t--) {
		memset(dp,-1,sizeof(dp));
		cin>>v>>k;
		tot=0;
		while(v) a[tot++]=v%10, v/=10;
		if(k==0) {
			for(ll i=0;i<=tot;i++) {
				if(a[i]<9) {
					__int128 ans=pw[i];
					pt(ans);
					break;
				}
			}
		}else pt(dfs(36,0,0));
	}
	return 0;
}