题目分析

```

include [HTML_REMOVED]

include [HTML_REMOVED]

include [HTML_REMOVED]

using namespace std;
const int N = 210;
int f[N][N] , w[N];

int n;
int main() {

cin >> n;

for (int i = 1;  i <= n ; i ++ ) {
    cin >> w[i];
    w[i + n] = w[i];
}

for (int len = 3 ; len <= n + 1 ; len ++ ) 
    for (int l = 1 ; l <= 2 * n - len + 1; l ++ ) {
        int r = l + len - 1;
        for (int k = l + 1 ; k < r ;  k ++ ) 
            f[l][r] = max(f[l][r] ,f[l][k] + f[k][r] + w[l] * w[k] * w[r]);
    }
int res = -0x3f3f3f;
for (int i = 1 ; i <= n ; i ++ )  res = max(res , f[i][n + i]);

cout << res;

return 0;
}

```