#include <bits/stdc++.h>   using namespace std;   long long a, b, c, l, tmp;   long long read() {     long long x = 0, f = 1;     char ch = getchar();     while (!isdigit(ch)) {       if (ch ==  - ) f = -1;       ch = getchar();     }     while (isdigit(ch)) x = x * 10 + ch -  0 , ch = getchar();     return x * f;   }   long long cal(long long x, long long y, long long z) {     if (x < y) return 0;     long long p = min(z, x - y);     return (p + 2) * (p + 1) / 2;   }   int main() {     a = read();     b = read();     c = read();     l = read();     for (int i = 0; i <= l; i++)       tmp += cal(a + i, b + c, l - i) + cal(b + i, a + c, l - i) +              cal(c + i, a + b, l - i);     printf( %I64d n , (l + 1) * (l + 2) * (l + 3) / 6 - tmp);     return 0;   }   