꿈꾸는공학도

http://topcoder.bgcoder.com/print.php?id=2390 TopCoder problem "DiamondMining" used in TCHS09 Round 3 (Division I Level Three)     A diamond mine is a matrix of ones and zeroes with R rows and C columns. A diamond is a pattern of ones forming the boundary of a 45-degree rotated square. The diamonds of size 1, 2, and 3 are shown below. size 1: size 2: size 3: 1 1 1 1 1 1 1 1 1topcoder.bgcoder.com..

https://leetcode.com/problems/largest-rectangle-in-histogram/description/Given an array of integers heights representing the histogram's bar height where the width of each bar is 1, return the area of the largest rectangle in the histogram. Example 1:Input: heights = [2,1,5,6,2,3]Output: 10Explanation: The above is a histogram where width of each bar is 1.The largest rectangle is shown in the re..

https://leetcode.com/problems/generate-parentheses/description/Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses. Example 1:Input: n = 3Output: ["((()))","(()())","(())()","()(())","()()()"]Example 2:Input: n = 1Output: ["()"] Constraints:1 간단한 Dynamic Programming 코딩 한 번 해보기!문제는 쉬워 보이나, 막상 코딩하려니까 좀 짜친다.  1. Python아래까지 풀다가 GG. 뭔가 뒤에 방법이 생각 안 난다..

https://leetcode.com/problems/min-cost-to-connect-all-points/description/You are given an array points representing integer coordinates of some points on a 2D-plane, where points[i] = [xi, yi].The cost of connecting two points [xi, yi] and [xj, yj] is the manhattan distance between them: |xi - xj| + |yi - yj|, where |val| denotes the absolute value of val.Return the minimum cost to make all poin..

https://leetcode.com/problems/valid-palindrome/description/A phrase is a palindrome if, after converting all uppercase letters into lowercase letters and removing all non-alphanumeric characters, it reads the same forward and backward. Alphanumeric characters include letters and numbers.Given a string s, return true if it is a palindrome, or false otherwise. Example 1:Input: s = "A man, a plan, ..

https://leetcode.com/problems/exam-room/description/There is an exam room with n seats in a single row labeled from 0 to n - 1.When a student enters the room, they must sit in the seat that maximizes the distance to the closest person. If there are multiple such seats, they sit in the seat with the lowest number. If no one is in the room, then the student sits at seat number 0.Design a class tha..

https://leetcode.com/problems/word-search/description/Given an m x n grid of characters board and a string word, return true if word exists in the grid.The word can be constructed from letters of sequentially adjacent cells, where adjacent cells are horizontally or vertically neighboring. The same letter cell may not be used more than once. Example 1:Input: board = [["A","B","C","E"],["S","F","C..

https://leetcode.com/problems/trapping-rain-water/description/Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap after raining. Example 1:Input: height = [0,1,0,2,1,0,1,3,2,1,2,1]Output: 6Explanation: The above elevation map (black section) is represented by array [0,1,0,2,1,0,1,3,2,1,2,1]. In this case, 6 units of rai..

list of list[int] 의 data type을 받아서 가장 긴 connected 1's length를 반환하는 함수를 만들어야 한다. Matrix 는 2차원이다보니까 m*n Matrix를 생각하면 되고, 주어진 2차원 Matrix에서 어떤 것을 0에서 1로 바꿀 지 잘 고민해야하고 x, y축 index 헷갈리지 않게 주의해야 한다. 이거때문에 index overflow로 애좀 먹음.. 꿀팁은 python deque만 있으면 queue / stack 다 구현할 수 있다는 것이고, python의 경우 if 문에서 0  그리고 맨 처음 언급했듯이, x / y축 len과 idx following을 잘 해야 한다. 이런 종류의 문제는 무작정 coding에 들어가지 말고, 머릿속으로 또는 빈 종이에 구조를..

https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/description/Suppose an array of length n sorted in ascending order is rotated between 1 and n times. For example, the array nums = [0,1,4,4,5,6,7] might become:[4,5,6,7,0,1,4] if it was rotated 4 times.[0,1,4,4,5,6,7] if it was rotated 7 times.Notice that rotating an array [a[0], a[1], a[2], ..., a[n-1]] 1 time results in the ..