class Solution def solve self st end if st end in self return self st

class Solution:
    d = {}
    
    def solve(self, st, end):
        if (st, end) in self.d:
            return self.d[(st, end)]
        
        
        max_v, sum_v = None, None
        for i in range(st, end):
            max_l, sum_l = self.solve(st, i)
            max_r, sum_r = self.solve(i+1, end)
            
            #print(self.d)
            max_c, sum_c = max(max_l, max_r), sum_l + sum_r + max_l*max_r
            if sum_v is None or sum_c < sum_v:
                max_v = max_c
                sum_v = sum_c
        
        self.d[(st, end)] = (max_v, sum_v)
        return max_v, sum_v
    
    
    def mctFromLeafValues(self, arr: List[int]) -> int:
        self.d = {}
        for i in range(len(arr)):
            self.d[(i, i)] = (arr[i], 0)
        
        max_v, ans = self.solve(0, len(arr)-1)
        return ans