꿈꾸는공학도

https://leetcode.com/problems/battleships-in-a-board/description/Given an m x n matrix board where each cell is a battleship 'X' or empty '.', return the number of the battleships on board.Battleships can only be placed horizontally or vertically on board. In other words, they can only be made of the shape 1 x k (1 row, k columns) or k x 1 (k rows, 1 column), where k can be of any size. At least..

https://leetcode.com/problems/maximal-square/description/Given an m x n binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. Example 1:Input: matrix = [["1","0","1","0","0"],["1","0","1","1","1"],["1","1","1","1","1"],["1","0","0","1","0"]]Output: 4Example 2:Input: matrix = [["0","1"],["1","0"]]Output: 1Example 3:Input: matrix = [["0"]]Output: 0..

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/min-cost-climbing-stairs/description/You are given an integer array cost where cost[i] is the cost of ith step on a staircase. Once you pay the cost, you can either climb one or two steps.You can either start from the step with index 0, or the step with index 1.Return the minimum cost to reach the top of the floor. Example 1:Input: cost = [10,15,20]Output: 15Explana..

https://leetcode.com/problems/stone-game-ix/description/Alice and Bob continue their games with stones. There is a row of n stones, and each stone has an associated value. You are given an integer array stones, where stones[i] is the value of the ith stone.Alice and Bob take turns, with Alice starting first. On each turn, the player may remove any stone from stones. The player who removes a ston..

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://app.codility.com/programmers/lessons/14-binary_search_algorithm/min_max_division/ MinMaxDivision coding task - Learn to Code - CodilityDivide array A into K blocks and minimize the largest sum of any block.app.codility.comYou are given integers K, M and a non-empty array A consisting of N integers. Every element of the array is not greater than M.You should divide this array into K block..

https://leetcode.com/problems/sort-list/description/Given the head of a linked list, return the list after sorting it in ascending order. Example 1:Input: head = [4,2,1,3]Output: [1,2,3,4]Example 2:Input: head = [-1,5,3,4,0]Output: [-1,0,3,4,5]Example 3:Input: head = []Output: [] Constraints:The number of nodes in the list is in the range [0, 5 * 104].-105  Follow up: Can you sort the linked lis..

https://leetcode.com/problems/minimum-add-to-make-parentheses-valid/description/?envType=daily-question&envId=2024-10-09A parentheses string is valid if and only if:It is the empty string,It can be written as AB (A concatenated with B), where A and B are valid strings, orIt can be written as (A), where A is a valid string.You are given a parentheses string s. In one move, you can insert a parent..

https://leetcode.com/problems/my-calendar-i/description/?envType=daily-question&envId=2024-09-26You are implementing a program to use as your calendar. We can add a new event if adding the event will not cause a double booking.A double booking happens when two events have some non-empty intersection (i.e., some moment is common to both events.).The event can be represented as a pair of integers ..