우사미 코딩

1. 문제링크 Sort List - LeetCode Can you solve this real interview question? Sort List - Given the head of a linked list, return the list after sorting it in ascending order. Example 1: [https://assets.leetcode.com/uploads/2020/09/14/sort_list_1.jpg] Input: head = [4,2,1,3] Output: [1, leetcode.com 지맘대로 생긴 ListNode를 오름차순으로 정렬하는 문제 2. Key Point - 제일 미니한 단위로 쪼갠다(재귀호출), merge한다 1) ListNode를 두개로 나눈다 - s..

1. 문제링크 Rotate Image - LeetCode Can you solve this real interview question? Rotate Image - You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise). You have to rotate the image in-place [https://en.wikipedia.org/wiki/In-place_algorithm], which m leetcode.com 2. 매트릭스 변환 2회 1) mat[i][j] mat[j][i] 1 2 3 1 4 7 4 5 6 -> 2 5 8 7 8 9 3 6 9 2) 각 row를 revers 1 4..

1. 문제링크 3Sum - LeetCode Can you solve this real interview question? 3Sum - Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j != k, and nums[i] + nums[j] + nums[k] == 0. Notice that the solution set must not contain du leetcode.com 이 주옥같은 문제는 제목부터 맘에 들지 않았지만 이제 이 문제랑 조금 친해졌으므로 "주옥같은" 타이틀을 빼주기로 했다 이 문제는 nums배열에서 3개의 원소의 합이 0이 되는 것들을 찾아..

1. 문제링크 Find Minimum in Rotated Sorted Array - LeetCode Can you solve this real interview question? Find Minimum in Rotated Sorted Array - Suppose an array of length n sorted in ascending order is rotated between 1 and n times. For example, the array nums = [0,1,2,4,5,6,7] might become: * [4,5,6,7,0,1,2] if it leetcode.com 2. Rotated Sorted Array는 무엇인가 - Sorted Array : 오름차순 배열 {1, 2, 3, 4, 5} - ..

1. 문제 링크 Happy Number - LeetCode Can you solve this real interview question? Happy Number - Write an algorithm to determine if a number n is happy. A happy number is a number defined by the following process: * Starting with any positive integer, replace the number by the sum of the squar leetcode.com 2. n을 한자리수로 쪼개서 제곱한 값을 모두 더한 값이 1이되면 해피넘버 input이 해피넘버이면 true 리턴, 아니면 false리턴 - Input: n = 19 1^..

https://leetcode.com/problems/reverse-bits/ Reverse Bits - LeetCode Can you solve this real interview question? Reverse Bits - Reverse bits of a given 32 bits unsigned integer. Note: * Note that in some languages, such as Java, there is no unsigned integer type. In this case, both input and output will be given as a signed leetcode.com 1. 개념정리 2. 코드 class Solution { public: uint32_t reverseBits(..

https://leetcode.com/problems/power-of-two/ Power of Two - LeetCode Can you solve this real interview question? Power of Two - Given an integer n, return true if it is a power of two. Otherwise, return false. An integer n is a power of two, if there exists an integer x such that n == 2x. Example 1: Input: n = 1 Output: leetcode.com 주어진 입력값이 2의 거듭제곱이면 true, 아니라면 false를 반환하는 문제 1) input : n = 1 ou..

https://leetcode.com/problems/number-of-1-bits/ Number of 1 Bits - LeetCode Can you solve this real interview question? Number of 1 Bits - Write a function that takes the binary representation of an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight [http://en.wikipedia.org/wiki/Hamming_w leetcode.com 32비트 2진수의 입력값에서 1비트의 개수를 구하는 문제 제약조건 Constraints: The..