func_code_string: #include <bits/stdc++.h>   using namespace std;   const double eps = 1e-6, pi = acos(-1);   const int N = 1e2 + 5, M = 1e9 + 7, SEGM = 4 * N, OO = 0x3f3f3f3f;   int t, n, m, v1, v2;   int mem[105][2005];   int main() {     scanf( %d%d%d%d , &v1, &v2, &n, &m);     if (v1 > v2) swap(v1, v2);     memset(mem, -OO, sizeof mem);     mem[0][v1] = v1;     for (int i = 1; i < n; ++i) {       for (int cur = v1; cur < 2005; ++cur) {         for (int j = 0; j <= m; ++j) {           if (cur + j < 2005)             mem[i][cur + j] = max(mem[i][cur + j], cur + j + mem[i - 1][cur]);           if (cur - j > -1)             mem[i][cur - j] = max(mem[i][cur - j], cur - j + mem[i - 1][cur]);         }       }     }     cout << mem[n - 1][v2];     return 0;   }   