func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long N = 4e3 + 5;   long long n, m, a[N], f[N][N];   long long solve(long long l, long long r) {     if (l > r) return 0;     long long p = 0;     for (long long i = l; i <= r; i++)       if (a[i] < a[p]) p = i;     long long ls = solve(l, p - 1), rs = solve(p + 1, r);     memset(f[p], -0x3f, sizeof(f[p]));     for (long long i = 0; i <= p - l; i++)       for (long long j = 0; j <= r - p; j++) {         f[p][i + j] = max(f[p][i + j], f[ls][i] + f[rs][j] - 2 * i * j * a[p]);         f[p][i + j + 1] =             max(f[p][i + j + 1], f[ls][i] + f[rs][j] - 2 * i * j * a[p] -                                      2 * (i + j) * a[p] + (m - 1) * a[p]);       }     return p;   }   signed main() {     cin >> n >> m;     a[0] = 1e18;     for (long long i = 1; i <= n; i++) cin >> a[i];     long long p = solve(1, n);     cout << f[p][m] << endl;   }   