func_code_string: #include <bits/stdc++.h>   using namespace std;   unsigned long long int a, b, c, l;   int main() {     ios::sync_with_stdio(false);     cin >> a >> b >> c >> l;     unsigned long long int ans = ((l + 3) * (l + 2) * (l + 1)) / (6);     for (int i = 0; i <= l; i++) {       if (a + i >= b + c) {         unsigned long long int x =             ((a + i - b - c) < (l - i) ? (a + i - b - c) : (l - i));         ans -= ((x + 2) * (x + 1)) / (2);       }     }     for (int i = 0; i <= l; i++) {       if (b + i >= a + c) {         unsigned long long int x =             ((b + i - a - c) < (l - i) ? (b + i - a - c) : (l - i));         ans -= ((x + 2) * (x + 1)) / (2);       }     }     for (int i = 0; i <= l; i++) {       if (c + i >= b + a) {         unsigned long long int x =             ((c + i - a - b) < (l - i) ? (c + i - a - b) : (l - i));         ans -= ((x + 2) * (x + 1)) / (2);       }     }     cout << ans << endl;     return 0;   }   