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

int main(){
 double x1,x2,y1,y2,d;

 cin >> x1 >> y1 >> x2 >> y2;

 d = sqrt(pow(x1-x2, 2) + pow(y1-y2, 2));

 printf("%lf\n", d);

 return 0;
}
#include <iostream>
using namespace std;

int main ()
{
    int p, q, r;
    cin >> p >> q >> r;
    cout << min(min(p + q, p + r), q + r);
}
