#include <bits/stdc++.h>

using namespace std;

#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define RFOR(i, a, b) for(int i = (a) - 1; i >= (b); i--)
#define SZ(a) int(a.size())
#define ALL(a) a.begin(), a.end()
#define PB push_back
#define MP make_pair
#define F first
#define S second

typedef long long LL;
typedef vector<int> VI;
typedef pair<int, int> PII;
typedef double db;



db d(int i, int j)
{
	return sqrt(i * i + j * j);
}

void check(int n, int m, int i, int j, db& ans)
{
	if(i == 0 && j == 0)
		return;
	if(i == n && j == m)
		return;
	if(gcd(i, j) != 1 || gcd(n - i, m - j) != 1)
		return;
	
	if((0 - i) * (j - m) == (i - n) * (0 - j))
		return;
	ans = min(ans, d(i, j) + d(n - i, m - j));
	
}

void solve()
{
	int n, m;
	cin >> n >> m;
	if(n < m)
		swap(n, m);
	
	db ans = 1e9;
	if(gcd(n, m) == 1)
		ans = d(n, m);
	
	FOR(x, 0, n + 1)
	{
		int My = (m * x) / n;
		
		FOR(y, max(0, My - 7), min(m, My + 7) + 1)
			check(n, m, x, y, ans);
	}
	cout << ans << "\n";
}




int main()
{
	ios::sync_with_stdio(0); 
	cin.tie(0);
	cout << fixed << setprecision(15);
	
	int t;
	cin >> t;
	while(t--)
		solve();
	
	
	
	
	
	return 0;
}