#include <bits/stdc++.h>
#define int long long
using namespace std;
int T, n, k, f[25][25][2], vis[25][25][2];
void solve() {
	scanf("%lld%lld", &n, &k);
	memset(f, 0x3f3f3f, sizeof(f));
	int now = 1;
	for(int i = 1;i <= 18;i++) {
		int g = n / now % 10;
		f[i][1][1] = min(f[i][1][1], now * (10 - g));
		if(g - 9) f[i][0][0] = min(f[i][0][0], now);  
		for(int j = 0;j <= k;j++) {
			f[i][j + 1][1] = min(f[i][j + 1][1], f[i - 1][j][0] + now * (10 - g));
			f[i][j][0] = min(f[i][j][0], f[i - 1][j][0]);	
			f[i][j + 1][1] = min(f[i][j + 1][1], f[i - 1][j][1] + now * (10 - 1 - g));
			if(g != 9) f[i][j][0] = min(f[i][j][0], f[i - 1][j][1]), vis[i][j][0] = 1;
		}
		now *= 10;
	}
	printf("%lld\n", min(f[18][k][1], f[18][k][0]));
}
signed main() {
	scanf("%lld", &T);
	while(T --) solve();
}