목록릿코드 (7)

소프트웨어에 대한 모든 것

LeetCode 풀기 - 1572. Matrix Diagonal Sum

1572. Matrix Diagonal Sum https://leetcode.com/problems/matrix-diagonal-sum/ Matrix Diagonal Sum - LeetCode Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview. leetcode.com 문제) 솔루션1) - Straight forward 왼쪽 상단에서 부터 오른쪽 하단으로 탐색하면서 더합니다. 오른쪽 상단에서 부터 왼쪽 하단으로 탐색하면서 더합니다. 만약 매트릭스가 row가 홀수 크기로 되어 있다면 중간에 원소를 두 번 더했..
알고리즘/LeetCode 2021. 12. 6. 08:19
LeetCode 풀기 - 20. Valid Parentheses

https://leetcode.com/problems/valid-parentheses/ Valid Parentheses - LeetCode Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview. leetcode.com 문제) 풀이 전략) 스택 자료구조 이용 솔루션1) class Solution: def isValid(self, s: str) -> bool: end_parentheses = [')', ']', '}'] stack = [] stack.append(s[0]) for c in s[1:]: if c i..
알고리즘/LeetCode 2021. 10. 31. 12:01
LeetCode 풀기 - 226. Invert Binary Tree

226. Invert Binary Tree 문제) Given the root of a binary tree, invert the tree, and return its root. 솔루션1) # Definition for a binary tree node. # class TreeNode: # def __init__(self, val=0, left=None, right=None): # self.val = val # self.left = left # self.right = right class Solution: def invertTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]: self.invert(root) return root def invert(se..
알고리즘/LeetCode 2021. 10. 29. 09:09
LeetCode 풀기 - 1684. Count the Number of Consistent Strings

1684. Count the Number of Consistent Strings 문제) 솔루션1) allowed 단어에 words가 있는지 탐색 O(n2) class Solution: def countConsistentStrings(self, allowed: str, words: List[str]) -> int: # Brute-Force count = 0 for word in words: count += 1 for i in range(len(word)): if word[i] not in allowed: count -= 1 break return count 솔루션2) class Solution: def countConsistentStrings(self, allowed: str, words: List[str..
알고리즘/LeetCode 2021. 10. 26. 07:56
LeetCode 풀이 - 1588. Sum of All Odd Length Subarrays

1588. Sum of All Odd Length Subarrays 문제) 솔루션1) class Solution: def sumOddLengthSubarrays(self, arr: List[int]) -> int: res = 0 n = len(arr) for j in range(1, len(arr)+1, 2): for i in range(n - j + 1): res += sum(arr[i:i+j]) return res
알고리즘/LeetCode 2021. 10. 25. 07:32
LeetCode 풀이 - 1512. Number of Good Pairs

1512. Number of Good Pairs 문제) 솔루션1) class Solution: def numIdenticalPairs(self, nums: List[int]) -> int: # brute-force # O(n2) count = 0 for i in range(len(nums)): for j in range(1, len(nums)): if nums[i] == nums[j] and i int: count_dict = defaultdict(int) count = 0 for num in nums: count += count..
알고리즘/LeetCode 2021. 10. 21. 01:00
LeetCode 풀이 - 1528. Shuffle String

Shuffle String 문제) 솔루션1) class Solution: def restoreString(self, s: str, indices: List[int]) -> str: res = [0] * len(s) for i1, i2 in enumerate(indices): res[i2] = s[i1] return ''.join(res) 솔루션2) class Solution: def restoreString(self, s: str, indices: List[int]) -> str: res = [0] * len(s) for idx, ch in enumerate(s): res[indices[idx]] = ch return ''.join(res)
알고리즘/LeetCode 2021. 10. 18. 22:52
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