Find the Sum of Maximum Subarray Products

Given an integer array, calculate the sum of each subarray's maximum value multiplied by its length, maintaining an overall time complexity of O(n). Input An integer array arr. Output The total sum of each subarray's maximum value multiplied by its length. Example Input: arr = [4,2,1,2] Output: 59 Example Explanation The subarray [4] has a maximum value 4 with length 1, giving a product of 4. The subarray [4, 2] has a maximum value 4 with length 2, giving a product of 8. The subarray [4, 2, 1] has a maximum value 4 with length 3, giving a product of 12. The subarray [4, 2, 1, 2] has a maximum value 4 with length 4, giving a product of 16. The subarray [2] has a maximum value 2 with length 1, giving a product of 2. The subarray [2, 1] has a maximum value 2 with length 2, giving a product of 4. The subarray [2, 1, 2] has a maximum value 2 with length 3, giving a product of 6. The subarray [1] has a maximum value 1 with length 1, giving a product of 1. The subarray [1, 2] has a maximum value 2 with length 2, giving a product of 4. The subarray [2] has a maximum value 2 with length 1, giving a product of 2. Sum of all products is 59. Example Input 4 2 1 2