Unit 1 Sprint 2 Swift Coding Challenge (2019-10-09 Wed)

u1s2-codingChallenge.swift

// INCOMPLETE AS OF 2019-10-09 08:46

func heightChecker(_ heights: [Int]) -> Int {
    // handle invalid list length
    if heights.count < 1 || heights.count > 100 {
        print("List is too long or short; must have between 1 and 100 students (inclusive).")
        return 0
    }
    
    var wrongStudents: [(index: Int, height: Int)] = []
    var lastCorrectStudent: (index: Int, height: Int) = (index: -1, height: 0)
    
    for i in 0 ..< heights.count - 1 {
        let currentStudent = (index: i, height: heights[i])
        
        // handle invaild heights
        if currentStudent.height < 1 || currentStudent.height > 100 {
            print("Student at array index \(i) is too tall or short; height must be between 1 and 100 (inclusive).")
            return 0
        }
        
        if currentStudent.height < lastCorrectStudent.height || currentStudent.height > heights[i + 1] {
            print("Student in wrong spot!")
            wrongStudents.append(currentStudent)
        } else {
            lastCorrectStudent = currentStudent
        }
    }
        
    print("Student array: \(heights)")
    print("Wrong students: \(wrongStudents)")
    print("Wrong students count: \(wrongStudents.count)")
    return wrongStudents.count
}

heightChecker([1,1,4,2,1,3])

//
// correct (?) implementation found ~10 minutes later
//

func simpleHeightChecker(_ heights: [Int]) -> Int {
    // handle invalid list length
    if heights.count < 1 || heights.count > 100 {
        print("List is too long or short; must have between 1 and 100 students (inclusive).")
        return 0
    }
    
    let sortedHeights = heights.sorted()
    var numWrongStudents = 0
    
    for i in 0 ..< heights.count {
        let currentStudentHeight = heights[i]
        
        // handle wrong heights
        if currentStudentHeight < 1 || currentStudentHeight > 100 {
            print("Height of student at index \(i) is too low or high; must be between 1 and 100 (inclusive).")
            return 0
        }
        
        if heights[i] != sortedHeights[i] {
            numWrongStudents += 1
        }
    }
    
    return numWrongStudents
}

print(simpleHeightChecker([1,1,4,2,1,3]))

So close! Great error handling though!