#include <iostream>
#include <cmath>
using namespace std;

double x1, y1, x2, y2;

int main()
{
    cout << "Input x1, y1: ";
    cin >> x1, y1;
    cout << "Input x2, y2: ";
    cin >> x2, y2;

    cout << "Distance between points: " << sqrt(pow(x2 - x1, 2) + pow(y2 - y1, 2));

    return 0;
}