`@`$\texttt{C++}$

#include <bits/stdc++.h>
#define int double
using namespace std;

signed main()
{
  int x, y, z; cin >> x >> y >> z;
  
  int a[3] = {x, y, z};
  
  sort(a, a + 3);
  
  int s = 0.0;
  if (a[0] + a[1] > a[2]) s = a[0] + a[1] - a[2];
  else s = a[2] - (a[0] + a[1]) + 0.00001;
  cout << fixed << setprecision(5) << s;
  return 0;
}

Học tốt!

$\color{Turquoise}{\triangleright \triangleright\ \color{ Turquoise}{\texttt{ItzPhuc} \triangleleft \triangleleft}}$