Swift Hackerrank Maximum Element in a Stack

I solve this problem in Swift. I'm not sure if using an array was the right way to approach it since the problem was on stacks. Any feedback on my code is appreciated:

You have an empty sequence, and you will be given N queries. Each query is one of these three types:

1 x -Push the element x into the stack.

2 -Delete the element present at the top of the stack.

3 -Print the maximum element in the stack.

import Foundation

/// Returns an integer read from one line of standard input.
func readInteger() -> Int {
    guard let line = readLine() else {
        fatalError("Unexpected end of input")
    }
    guard let i = Int(line) else {
        fatalError("Invalid integer in input")
    }
    return i
}

// Returns an array of integers read from one line of standard input.
func readIntegers() -> [Int] {
    guard let line = readLine() else {
        fatalError("Unexpected end of input")
    }
    return line.componentsSeparatedByString(" ").map{ Int($0)! }
}

// returns maximum element in stack
func maxElement() {
    let queries = readInteger()
    var stack = [Int]()

    // loops through each query
    for _ in 0..<queries {
        let input = readIntegers()
        let type = input[0]
        switch type {
        case 1:
            // 2nd input only given when type is 1
            let element = input[1]
            stack.append(element)
        case 2:
            // deletes element at top of the stack
            // stack is LIFO
            stack.removeLast()
        case 3:
            if let maxElement = stack.maxElement() {
                print(maxElement)
            }
        default:
            fatalError("Unknown input type")
        }
    }
}

maxElement()