// 

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

using ll = long long;

#define rep(i, n) for (int i=0; i<(int)(n); ++(i))
#define rep3(i, m, n) for (int i=(m); (i)<(int)(n); ++(i))
#define repr(i, n) for (int i=(int)(n)-1; (i)>=0; --(i))
#define rep3r(i, m, n) for (int i=(int)(n)-1; (i)>=(int)(m); --(i))
#define all(x) (x).begin(), (x).end()

const int INF = (int)(1e9);

int main() {
	int t0;
	cin >> t0;
	rep(i0, t0) {
		ll n;
		string s;
		cin >> n >> s;
		int pi = s.find('.'), si = stoi(s.substr(0, pi)) * 1000 + stoi(s.substr(pi+1));
		ll li = 0, ri = n+1;
		while (ri-li > 1) {
			ll ci = li + (ri-li) / 2, lval = si * ci, rval = (si+1) * ci;
			if (lval/1000==rval/1000 && lval%1000!=0) li = ci;
			else ri = ci;
		}
		ll res = (n+1) - ri;
		cout << res << endl;
	}
	return 0;
}