/Day 1: Interquartile Range

Day 1: Interquartile Range

import Foundation
//Day 1: Interquartile Range



func medianFunc(numbers: [Int]) -> Double {
    let sortedNumbers = numbers.sorted(by: { num1, num2 in
        return num1 < num2 })
    
    let midIndex = numbers.count / 2
    var median = Double(sortedNumbers[midIndex])
    if(numbers.count % 2 == 0){
        median = Double(sortedNumbers[midIndex] + sortedNumbers[midIndex - 1]) / Double(2)
    }
    
    return median
}

func quartiles(numbers: [Int]) -> Double {
    let sortedNumbers = numbers.sorted(by: { num1, num2 in
        return num1 < num2 })
    var midIndex = sortedNumbers.count / 2
    
    var lowerHalf = [Int]()
    for i in 0..<midIndex {
      lowerHalf.append(sortedNumbers[i])
    }
    
   
    if(sortedNumbers.count % 2 == 0){
       
        midIndex = midIndex - 1
    }
    
    var UpperHalf = [Int]()
    for i in (midIndex+1)..<sortedNumbers.count {
        UpperHalf.append(sortedNumbers[i])
    }
//    print(sortedNumbers)
//    print(UpperHalf)
  

    return medianFunc(numbers: UpperHalf) - medianFunc(numbers: lowerHalf)
}
func interQuartiles(numbers: [Int], freq : [Int]) -> Double {
    var arr : [Int] = [Int]()
    for i in 0..<numbers.count
    {
        for _ in 0..<freq[i]{
             arr.append(numbers[i])
        }
    }
    return quartiles(numbers: arr)
}
//interQuartiles(numbers: [6, 12, 8, 10, 20, 16], freq: [5, 4, 3, 2, 1 ,5])

let stdout = ProcessInfo.processInfo.environment["OUTPUT_PATH"]!
FileManager.default.createFile(atPath: stdout, contents: nil, attributes: nil)
let fileHandle = FileHandle(forWritingAtPath: stdout)!

guard let n = Int((readLine()?.trimmingCharacters(in: .whitespacesAndNewlines))!)
    else { fatalError("Bad input") }

guard let arTemp = readLine() else { fatalError("Bad input") }
let ar: [Int] = arTemp.split(separator: " ").map {
    if let arItem = Int($0.trimmingCharacters(in: .whitespacesAndNewlines)) {
        return arItem
    } else { fatalError("Bad input") }
}

guard let arTemp2 = readLine() else { fatalError("Bad input") }
let ar2: [Int] = arTemp2.split(separator: " ").map {
    if let arItem = Int($0.trimmingCharacters(in: .whitespacesAndNewlines)) {
        return arItem
    } else { fatalError("Bad input") }
}

guard ar.count == n else { fatalError("Bad input") }
let resultvalue = interQuartiles(numbers: ar, freq: ar2)

fileHandle.write(String(resultvalue).data(using: .utf8)!)
fileHandle.write("\n".data(using: .utf8)!)