An array A consisting of N integers is given. Rotation of the array means that each element is shifted right by one index, and the last element of the array is moved to the first place. For example, the rotation of array A = [3, 8, 9, 7, 6] is [6, 3, 8, 9, 7] (elements are shifted right by one index and 6 is moved to the first place).
The goal is to rotate array A K times; that is, each element of A will be shifted to the right K times.
Write a function:
public func solution(_ A : inout [Int], _ K : Int) -> [Int]
that, given an array A consisting of N integers and an integer K, returns the array A rotated K times.
For example, given
A = [3, 8, 9, 7, 6] K = 3the function should return [9, 7, 6, 3, 8]. Three rotations were made:
[3, 8, 9, 7, 6] -> [6, 3, 8, 9, 7] [6, 3, 8, 9, 7] -> [7, 6, 3, 8, 9] [7, 6, 3, 8, 9] -> [9, 7, 6, 3, 8]For another example, given
A = [0, 0, 0] K = 1the function should return [0, 0, 0]
Given
A = [1, 2, 3, 4] K = 4the function should return [1, 2, 3, 4]
Assume that:
- N and K are integers within the range [0..100];
- each element of array A is an integer within the range [−1,000..1,000].
In your solution, focus on correctness. The performance of your solution will not be the focus of the assessment.
// you can also use imports, for example:
// import Foundation
// import Glibc
// you can write to stdout for debugging purposes, e.g.
// print("this is a debug message")
public func solution(inout aArray : [Int], _ kTimes : Int) -> [Int] {
// write your code in Swift 2.2 (Linux)
guard aArray.count > 0 else {return aArray}
let nSize = aArray.count
// start with the dumb solution:
var rotating = aArray
for i in 0..<kTimes {
// get the last element of the array:
let last = rotating.removeLast()
rotating = [last] + rotating
}
return rotating
}
// you can also use imports, for example:
// import Foundation
// import Glibc
// you can write to stdout for debugging purposes, e.g.
// print("this is a debug message")
public func solution(inout aArray : [Int], _ kTimes : Int) -> [Int] {
guard aArray.count > 0 else {return aArray}
var rotating = aArray // make mutable
for _ in 0..<kTimes {
// get the last element of the array:
let last = rotating.removeLast()
// append to rotating
rotating = [last] + rotating
}
return rotating
}
// you can also use imports, for example:
// import Foundation
// import Glibc
// you can write to stdout for debugging purposes, e.g.
// print("this is a debug message")
public func solution(inout aArray : [Int], _ kTimes : Int) -> [Int] {
guard aArray.count > 0 else {return aArray}
var rotating = aArray // make mutable
for _ in 0..<kTimes {
// get the last element of the array:
let last = rotating.removeLast()
// append to rotating
rotating = [last] + rotating
}
return rotating
}
The solution obtained perfect score.