#include<bits/stdc++.h>
#include<unordered_map>
#include<unordered_set>
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
#define debug(a) cout<<a<<'\n'
#define Pll pair<ll,ll>
#define PII pair<int,int>
#define ft first
#define sd second
#define vec vector
#define pushk push_back
#define ump unordered_map
#define pl p<<1
#define pr p<<1|1
using namespace std;
const int N = 15 + 10, M = 1e4 + 10, mod = 1e9 + 7;
const ll inf = 1e18;
const ld eps = 1e-13;
int mov[4][2] = { {0,1},{1,0},{-1,0},{0,-1} }, dx, dy, _ = 1, __ = 1;
void bout(bool f) {
	if (f)cout << "Yes\n";
	else cout << "No\n";
}
ll n, m, k;
ull p[25],dp[25][2],pre[25][2];

void ini() {
	p[0]=1;
	for(int i=1;i<=19;++i)p[i]=10*p[i-1];
}
void solve() {
	string s;
	cin>>s>>k;
	if(__>5){
		if(__-_==17){
			cout<<s<<' '<<k;
		}
		return;
	}
	reverse(s.begin(),s.end());
	memset(dp,0x3f,sizeof dp);
	dp[0][0]=0;
	ll  x,y,z;
	for(int i=0;i<s.length();++i){
		memcpy(pre,dp,sizeof dp);
		memset(dp,0x3f,sizeof dp);
		x=s[i]-'0';
		if(x==9){
			for(int j=1;j<=i+1;++j){
				dp[j][0]=pre[j][0];
				dp[j][1]=min(pre[j-1][0]+p[i],pre[j-1][1]);
			}
		}else{
			for(int j=1;j<=i+1;++j){
				dp[j][0]=min(pre[j][0],pre[j][1]);
				if(x)dp[j][1]=min(pre[j-1][0]+(10-x)*p[i],pre[j-1][1]+(9-x)*p[i]);
				else dp[j][1]=pre[j-1][1]+(9-x)*p[i];
			}
		}
		dp[0][0]=0;
	}
	if(!k){
		for(int i=0;i<=18;++i){
			if(i<s.length())x=s[i]-'0';
			else x=0;
			if(x<9){
				cout<<p[i]<<'\n';
				break;
			}
		}
	}
	else {
		x=min(dp[k][0],dp[k][1]);
		if(x<dp[0][1]){
			cout<<x<<'\n';
		}else{
			for(int i=k;i>=0;--i){
				if(dp[i][1]>=dp[0][1])cout<<'9';
				else{
					cout<<dp[i][1]<<'\n';
					break;
				}
			}
		}
	}
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
#ifndef ONLINE_JUDGE
	streambuf* cinbackup = cin.rdbuf(), * coutbackup = cout.rdbuf();
	ifstream fin("in.txt");
	ofstream fout("out.txt");
	cin.rdbuf(fin.rdbuf());
	cout.rdbuf(fout.rdbuf());
#endif
	cin >> _;
	__ = _;
	ini();
	while (_--) {
		solve();
	}
	return 0;
}