CPP0112 - KHOẢNG CÁCH

#include <iostream>
#include<math.h>
#include<iomanip>
using namespace std;
int main()
{
	int t;
	cin >> t;
	while (t--) {
		double a, b, c, d;
		cin >> a >> b >> c >> d;
		cout << setprecision(4) << fixed << (double)sqrt((a - c) * (a - c) + (b - d) * (b - d)) << endl;
	}
}