#include <bits/stdc++.h>   using namespace std;   int a[3];   int main() {     cin >> a[0] >> a[1] >> a[2];     sort(a + 0, a + 3);     int res = 0;     while ((a[0] + a[1]) <= a[2]) {       a[0]++;       res++;     }     cout << res;   }   