morning code challenge week 11

codeChallengeWeek11

import Foundation

func sameNumberOfBinaryOnes(_ number: Int) -> (Int, Int?) {
    let stringNumInBinary = "\(number, radix: .binary)"
    var numOfOneInNum: Int = 0
    for element in stringNumInBinary {
        if element == "1" {
            numOfOneInNum += 1
        }
    }
    var highNum: Int = 0
    var lowNum: Int?
    for i in number + 1 ..< Int.max {
        let iStringBinary = "\(i, radix: .binary)"
        var numOfOne: Int = 0
        for element in iStringBinary {
            if element == "1" {
                numOfOne += 1
            }
        }
        if numOfOneInNum == numOfOne {
            highNum = i
            break
        }
    }
    
    for i in stride(from: number - 1, through: 1, by: -1) {
        let iStringBinary = "\(i, radix: .binary)"
        var numOfOne: Int = 0
        for element in iStringBinary {
            if element == "1" {
                numOfOne += 1
            }
        }
        if numOfOneInNum == numOfOne {
            lowNum = i
            break
        }
    }
    return(highNum, lowNum)
}
public extension String.StringInterpolation {
    /// Represents a single numeric radix
    enum Radix: Int {
        case binary = 2, octal = 8, decimal = 10, hex = 16
        
        /// Returns a radix's optional prefix
        var prefix: String {
            return [.binary: "0b", .octal: "0o", .hex: "0x"][self, default: ""]
        }
    }
    
    /// Return padded version of the value using a specified radix
    mutating func appendInterpolation<I: BinaryInteger>(_ value: I, radix: Radix, prefix: Bool = false, toWidth width: Int = 0) {
        
        // Values are uppercased, producing `FF` instead of `ff`
        var string = String(value, radix: radix.rawValue).uppercased()
        
        // Strings are pre-padded with 0 to match target widths
        if string.count < width {
            string = String(repeating: "0", count: max(0, width - string.count)) + string
        }
        
        // Prefixes use lower case, sourced from `String.StringInterpolation.Radix`
        if prefix {
            string = radix.prefix + string
        }
        
        appendInterpolation(string)
    }
}
sameNumberOfBinaryOnes(12)
sameNumberOfBinaryOnes(28)
sameNumberOfBinaryOnes(3)