[问] 错哪了！！！？？？

#include<bits/stdc++.h>
#define int long long 
using namespace std;
int a[210];
int f[210][210];
signed main(){
    int n;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
        a[i+n] = a[i];
    }
 
    for(int len=2;len<=n*2;len++){
        for(int l=1;l<=n*2-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] + a[l]*a[k]*a[r]);
            }
        }
    }
    cout<<f[1][n]/2;
    return 0;
}