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

int maxRotateFunction(int* nums, int numsSize) {
    if (numsSize <= 1) return 0;
    
    // Calculate F(0) and total sum
    long long fVal = 0, totalSum = 0;
    for (int i = 0; i < numsSize; i++) {
        fVal += (long long)i * nums[i];
        totalSum += nums[i];
    }
    
    long long maxVal = fVal;
    
    // Use the pattern: F(k+1) = F(k) + sum - n * nums[n-k-1]
    for (int k = 1; k < numsSize; k++) {
        fVal = fVal + totalSum - (long long)numsSize * nums[numsSize - k];
        if (fVal > maxVal) {
            maxVal = fVal;
        }
    }
    
    return (int)maxVal;
}

int main() {
    char line[10000];
    fgets(line, sizeof(line), stdin);
    
    int nums[1000];
    int size = 0;
    char* token = strtok(line + 1, ",]");
    while (token != NULL) {
        nums[size++] = atoi(token);
        token = strtok(NULL, ",]");
    }
    
    printf("%d\n", maxRotateFunction(nums, size));
    return 0;
}