LeetCode 48. Rotate Image
Problem: You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note: You have to rotate the image in-place, which means you have to modify the input 2D matrix directly. DO NOT allocate another 2D matrix and do the rotation. Example 1: Given input matrix = [ [1,2,3], [4,5,6], [7,8,9] ], rotate the input matrix in-place such that it becomes: [ [7,4,1],..
2020. 5. 22.
LeetCode 283. Move Zeroes
Problem: Given an array nums, write a function to move all 0's to the end of it while maintaining the relative order of the non-zero elements. Example: Input: [0,1,0,3,12] Output: [1,3,12,0,0] -Summary- Used two-pointer using two loops. 1. set 1 pointer of for loop for the zero-value index in the nums list. 2. If zero index found, then we loop starting from the next index then find the number th..
2020. 5. 22.
LeetCode 189. Rotate Array
Problem: Given an array, rotate the array to the right by k steps, where k is non-negative. Follow up: Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem. Could you do it in-place with O(1) extra space? 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 step..
2020. 5. 22.
