#include <bits/stdc++.h>   using namespace std;   long long ans;   int main() {     vector<int> a(3);     for (size_t i = 0; i < 3; i++) {       cin >> a[i];     }     sort(a.begin(), a.end());     cout << ((a[1] + a[0] > a[2]) ? 0 : (-a[1] - a[0] + a[2] + 1));   }   