#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int solution(int* nums, int size) {
    // Add padding balloons with value 1
    int* balloons = (int*)malloc((size + 2) * sizeof(int));
    balloons[0] = 1;
    balloons[size + 1] = 1;
    for (int i = 0; i < size; i++) {
        balloons[i + 1] = nums[i];
    }
    
    int n = size + 2;
    // dp[i][j] represents max coins from range (i, j)
    int** dp = (int**)malloc(n * sizeof(int*));
    for (int i = 0; i < n; i++) {
        dp[i] = (int*)calloc(n, sizeof(int));
    }
    
    // Fill table by increasing range length
    for (int length = 2; length < n; length++) {
        for (int left = 0; left < n - length; left++) {
            int right = left + length;
            // Try each balloon k as the last one to burst in range (left, right)
            for (int k = left + 1; k < right; k++) {
                int coins = balloons[left] * balloons[k] * balloons[right]
                          + dp[left][k] + dp[k][right];
                if (coins > dp[left][right]) {
                    dp[left][right] = coins;
                }
            }
        }
    }
    
    int result = dp[0][n-1];
    
    for (int i = 0; i < n; i++) {
        free(dp[i]);
    }
    free(dp);
    free(balloons);
    
    return result;
}

int main() {
    char line[1000];
    fgets(line, sizeof(line), stdin);
    
    int nums[500];
    int size = 0;
    char* token = strtok(line, "[],\n");
    while (token != NULL) {
        nums[size++] = atoi(token);
        token = strtok(NULL, "[],\n");
    }
    
    int result = solution(nums, size);
    printf("%d\n", result);
    
    return 0;
}