Given nested array calculate the depth sum and provide time and space complexity.
Input: [1, 2, [4, 5, [7], 8], 9]
Output: 1 + 2 + 2*(4 + 5 + 3*7 + 8) + 9 = 88

Question

Given nested array calculate the depth sum and provide time and space complexity.  
Input:  [1, 2, [4, 5, [7], 8], 9] 
Output:  1 + 2 + 2*(4 + 5 + 3*7 + 8) + 9 = 88

Avi T · Accepted Answer

My answer in Swift:

let nestedArray = [1 , 2, [4, 5, [7], 8], 9] as [Any]


func calculateArray(array : [Any], level : Int)->Int {
    print(array)
    print(level)
    var sum = 0
    for i in array {
        if i is Int {
            sum += i as! Int
        }
        
        if i is [Any] {
            sum += calculateArray(array: i as! [Any], level: level + 1)
        }
    }
    
    return level * sum
}

calculateArray(array: nestedArray, level: 1)

Name · Answer

The input is strictly [Any]. Solution if you can't adjust param(Swift):

    func nestedSum(_ array : [Any]) -> Int {
        var sum = 0
        var multiplier : CGFloat = 1
        var flexibleArray = array
        if let prevMultiplier = array[0] as? CGFloat {
            multiplier = prevMultiplier
            flexibleArray.remove(at: 0)
        }
        for eachValue in flexibleArray {
            if eachValue is Int {
                sum += eachValue as! Int
            } else if eachValue is [Any] {
                multiplier += 1
                var newArray = eachValue as! [Any]
                newArray.insert(multiplier, at: 0)
                sum += Int(multiplier) * nestedSum(newArray)
            }
        }
        return total
    }

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