C++ :

#include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;
int main()
{
    int t;
    double a,b,c,d;
    cin>>t;
    while(t--)
    {
        cin>>a>>b>>c>>d;
        printf("%.2lf\n",sqrt((a-c)*(a-c)+(b-d)*(b-d)));
    }
    return 0;
}

Python :

# coding=utf-8
import sys


def main():
    n = sys.stdin.readline().strip()
    for i in range(int(n)):
        cnt = sys.stdin.readline().strip()
        if not cnt:
            break
        a,b,c,d= map(int,cnt.split(' '))
        h=(a-c)*(a-c)+(b-d)*(b-d)
        zh = h ** 0.5
        xh=format(float(zh), '.2f')
        print(xh)






if __name__ == '__main__':
    main()