#include <bits/stdc++.h>
#define ll long long
using namespace std;
 
 
 
ll matrixMul(int start, int end, vector<int> &arr) {
 
    if(start == end) {
        return 0;
    }
 
    ll minCost = INT_MAX;
    for(int i = start; i < end; i++) {
        ll cost = (arr[start - 1] * arr[i] * arr[end]) + matrixMul(start, i, arr) + matrixMul(i + 1, end, arr);
        minCost = min(minCost, cost);
    }
 
    return minCost == INT_MAX? 0: minCost;
}
 
int main() {
    vector<int> arr;
    int n;
    cin>> n;
    for(int i = 0; i < n; i++) {
        int ele;
        cin>> ele;
        arr.push_back(ele);
    }
 
    cout<< matrixMul(1, n - 1, arr);
	return 0;
}
 
 

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