#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cmath>
#include<cassert>
#define int long long
#define RI register int
#define CI const int&
using namespace std;
int t,n,m;
signed main()
{
    for (scanf("%lld",&t);t;--t)
    {
        scanf("%lld%lld",&n,&m);
        int g=__gcd(n,m);
        auto dist=[&](CI x,CI y)
        {
            return sqrt(1LL*x*x+1LL*y*y);
        };
        if (g==1) { printf("%.15lf\n",dist(n,m)); continue; }
        double ans=1e18;
        for (RI p=1;p<=n;++p)
        {
            int q=1LL*m*p/n;
            if (__gcd(p,q)!=1||__gcd(n-p,m-q)!=1||(p==n-p&&q==m-q))
            {
                //do nothing
            } else ans=min(ans,dist(p,q)+dist(n-p,m-q));
            for (RI j=0;j<1;++j)
            {
                --q; if (q<0) break;
                if (__gcd(p,q)!=1||__gcd(n-p,m-q)!=1||(p==n-p&&q==m-q))
                {
                    //do nothing
                } else ans=min(ans,dist(p,q)+dist(n-p,m-q));
            }
        }
        for (RI q=1;q<=m;++q)
        {
            int p=1LL*n*q/m;
            if (__gcd(p,q)!=1||__gcd(n-p,m-q)!=1||(p==n-p&&q==m-q))
            {
                //do nothing
            } else ans=min(ans,dist(p,q)+dist(n-p,m-q));
            for (RI j=0;j<1;++j)
            {
                --p; if (p<0) break;
                if (__gcd(p,q)!=1||__gcd(n-p,m-q)!=1||(p==n-p&&q==m-q))
                {
                    //do nothing
                } else ans=min(ans,dist(p,q)+dist(n-p,m-q));
            }
        }
        printf("%.15lf\n",ans);
    }
    return 0;
}