#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef double db;
typedef pair<int, int> pi;

#define fi first
#define se second
#define V vector
#define pb push_back
#define all1(x) (x).begin() + 1, (x).end()
#define all0(x) (x).begin(), (x).end()

db dis2(int x, int y, int a, int b) {
    return sqrt(1LL * (x - a) * (x - a) + 1LL * (y - b) * (y - b));
}

clock_t startTime;
double getCurrentTime() {
	return (double)(clock() - startTime) / CLOCKS_PER_SEC;
}

mt19937 mrand(chrono::steady_clock().now().time_since_epoch().count());

void solve() {
    cout << fixed << setprecision(12);
    int n, m; cin >> n >> m;
    startTime = clock();
    if(__gcd(n, m) == 1) {
        cout << dis2(0, 0, n, m) << endl;
        return;
    }
    db ans = 1e18;
    for(LL i = 0; i <= n; i++) {
        LL base = (1LL * m * i + n - 1) / n - 1;
        LL x = base;

        while(x >= 0 && (__gcd(i, x) != 1 || __gcd(n - i, m - x) != 1)) x--;
        if(x >= 0) {
            ans = min(ans, dis2(0, 0, i, x) + dis2(i, x, n, m));
            // cout << i << " " << x << endl;
        }

        // cout << i << " " << x << endl;

        x = base + 1;
        if(1LL * x * n == 1LL * i * m) x++;
        while(x <= m && (__gcd(i, x) != 1 || __gcd(n - i, m - x) != 1)) x++;
        if(x <= m) {
            ans = min(ans, dis2(0, 0, i, x) + dis2(i, x, n, m));
            // cout << i << " " << x << endl;
        }

        // if(i % 100 == 0) cout << i << endl;
    }
    cout << ans << endl;
    // cout << getCurrentTime() << endl;
}

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    int t; cin >> t;
    while(t--)
    solve();
}