Codeforces Round #516 Div.2 A. Make a triangle!(水题)

#include <bits/stdc++.h>
#define ll long long
using namespace std;
int pre[3];

int main()
{
  for(int i=0;i<3;i++){
    cin>>pre[i];
  }
  sort(pre, pre + 3);
  if(pre[2] < pre[1] + pre[0]){
    puts("0");
  }
  else{
    printf("%d\n",pre[2] - (pre[0] + pre[1]) + 1);
  }
  return 0;
}