Task description

Solution

First, I convert the input N to a binary string using String(value, radix: 2). Then, in a for loop, I check each character of the binary string. During the loop, if the character is "0", I add 1 to the tmp variable for temporary checking (because it is not yet confirmed as a gap).

At the end of the iteration, if the character is "1", I check if the tmp value is greater than the cnt value and update the cnt variable if it is. I also reset the tmp value to 0 each time the character is "1".

import Foundation
import Glibc

// you can write to stdout for debugging purposes, e.g.
// print("this is a debug message")

public func solution(_ N : Int) -> Int {
    // count for maximum gap
    var cnt: Int = 0

    var tmp: Int = 0
    // Implement your solution here

    // binary string value
    let bin = String(N,radix:2)

    if !bin.contains("0") {
        return 0
    }

    // find maximum value of gap
    for s in bin {
        if s == "0" {
            tmp += 1
        } else {
            // check tmp is bigger than cnt
            if tmp >= cnt {
                cnt = tmp
            }
            tmp = 0
        }
    }

    return cnt
}