凸多边形的划分

n = eval(input())
a = list(map(int, input().split()))
a += a
a = [0] + a
dp = [[1e40 for i in range(200)] for j in range(200)]
for i in range(1, 2 * n + 1):
    dp[i][i + 1] = 0
for len in range(2, n):
    for l in range(1, 2 * n - len + 1):
        r = l + len
        for k in range(l + 1, r):
            dp[l][r] = min(dp[l][r], dp[l][k] + dp[k][r] + a[l] * a[r] * a[k])
ans = dp[1][n]
for i in range(1, n + 1):
    ans = min(ans, dp[i][i + n - 1])
print(ans)