#include <stdio.h>

long long n, v[512], cost[512][512], i, j, z, sum;

long long min(long long a, long long b) {
	if (a < b) return a;
	return b;
}

int main() {
	freopen("podm.in", "r", stdin);
	freopen("podm.out", "w", stdout);
	scanf("%lld", &n);
	scanf("%lld", &v[0]);
	for (i = 1; i <= n; ++i) {
		scanf("%lld", &v[i]);
	}
	for (i = 1; i <= n; ++i) cost[i][i] = 0;
	for (i = 1; i <  n; ++i) cost[i][i + 1] = v[i - 1] * v[i] * v[i + 1];
	for (i = 2; i < n; ++i) {
		for (j = 1; j <= n - i; ++j) {
			cost[j][i + j] = 200000000000000LL;
			for (z = j; z <= j + i - 1; ++z) {
				sum = (cost[j][z] + cost[z + 1][i + j] + (v[j - 1] * v[z] * v[i + j]));
				if (cost[j][i + j] > sum) {
					cost[j][i + j] = sum;
				}
			}
		}
	}
	printf("%lld", cost[1][n]);
	return 0;
}