[leetCode] 189. Rotate Array

🎆 Description

Given an array, rotate the array to the right by k steps, 
where k is non-negative.

Example 1:

Input: nums = [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps to the right: [7,1,2,3,4,5,6]
rotate 2 steps to the right: [6,7,1,2,3,4,5]
rotate 3 steps to the right: [5,6,7,1,2,3,4]
Example 2:

Input: nums = [-1,-100,3,99], k = 2
Output: [3,99,-1,-100]
Explanation: 
rotate 1 steps to the right: [99,-1,-100,3]
rotate 2 steps to the right: [3,99,-1,-100]

🎇 Solution

이게 어떻게 two pointers로 풀 수 있는 건지 모르겠다.

❌ approach 1 - time imit exceeded

var rotate = function(nums, k) {
    for (i=0; i<k; i++) {
        nums.unshift(nums.pop());
    }
};

다음 two pointers 문제들을 풀어보고 다시 돌아와보자.