From c784f39e769d1f421811c70c8c905ae7b35b8641 Mon Sep 17 00:00:00 2001 From: hu6r1s Date: Tue, 9 Sep 2025 14:53:44 +0900 Subject: [PATCH 1/6] feat: Solve revser-bits problem --- reverse-bits/hu6r1s.py | 6 ++++++ 1 file changed, 6 insertions(+) create mode 100644 reverse-bits/hu6r1s.py diff --git a/reverse-bits/hu6r1s.py b/reverse-bits/hu6r1s.py new file mode 100644 index 000000000..c418dccc3 --- /dev/null +++ b/reverse-bits/hu6r1s.py @@ -0,0 +1,6 @@ +class Solution: + """ + binary로 변환 후 zfill로 32자리를 맞춰주고 reverse시킨다. + """ + def reverseBits(self, n: int) -> int: + return int(bin(n)[2:].zfill(32)[::-1], 2) From e31317f66b1677df87652f4e1375cee60305946a Mon Sep 17 00:00:00 2001 From: hu6r1s Date: Thu, 11 Sep 2025 10:33:14 +0900 Subject: [PATCH 2/6] feat: Solve clone-graph problem --- clone-graph/hu6r1s.py | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 clone-graph/hu6r1s.py diff --git a/clone-graph/hu6r1s.py b/clone-graph/hu6r1s.py new file mode 100644 index 000000000..bae60f776 --- /dev/null +++ b/clone-graph/hu6r1s.py @@ -0,0 +1,28 @@ +""" +# Definition for a Node. +class Node: + def __init__(self, val = 0, neighbors = None): + self.val = val + self.neighbors = neighbors if neighbors is not None else [] +""" + +from typing import Optional +class Solution: + def cloneGraph(self, node: Optional['Node']) -> Optional['Node']: + if not node: + return None + + visited = [None] * 101 + + def dfs(n): + if visited[n.val] is not None: + return visited[n.val] + + copy = Node(n.val, []) + visited[n.val] = copy + + for nei in n.neighbors: + copy.neighbors.append(dfs(nei)) + return copy + + return dfs(node) From da32e179181e53c163ec74f274b7dc63988fbc99 Mon Sep 17 00:00:00 2001 From: hu6r1s Date: Thu, 11 Sep 2025 11:07:40 +0900 Subject: [PATCH 3/6] feat: Solve palindromic-substrings problem --- palindromic-substrings/hu6r1s.py | 12 ++++++++++++ 1 file changed, 12 insertions(+) create mode 100644 palindromic-substrings/hu6r1s.py diff --git a/palindromic-substrings/hu6r1s.py b/palindromic-substrings/hu6r1s.py new file mode 100644 index 000000000..021fe017d --- /dev/null +++ b/palindromic-substrings/hu6r1s.py @@ -0,0 +1,12 @@ +class Solution: + """ + + """ + def countSubstrings(self, s: str) -> int: + cnt = [] + for i in range(len(s)): + for j in range(i, len(s)): + sub = s[i:j+1] + if sub and sub == sub[::-1]: + cnt.append(sub) + return len(cnt) From 824d1a095ec7cfbffa170509d46a16f8fba4f2f8 Mon Sep 17 00:00:00 2001 From: hu6r1s Date: Thu, 11 Sep 2025 11:28:41 +0900 Subject: [PATCH 4/6] feat: Solve palindromic-substrings problem --- palindromic-substrings/hu6r1s.py | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/palindromic-substrings/hu6r1s.py b/palindromic-substrings/hu6r1s.py index 021fe017d..8f3993439 100644 --- a/palindromic-substrings/hu6r1s.py +++ b/palindromic-substrings/hu6r1s.py @@ -1,12 +1,13 @@ class Solution: """ - + 브루트포스로 모두 탐색하면서 집어넣는 방법 + O(n^2) """ - def countSubstrings(self, s: str) -> int: - cnt = [] - for i in range(len(s)): - for j in range(i, len(s)): - sub = s[i:j+1] - if sub and sub == sub[::-1]: - cnt.append(sub) - return len(cnt) + def countSubstrings(self, s: str) -> int: + cnt = [] + for i in range(len(s)): + for j in range(i, len(s)): + sub = s[i:j+1] + if sub and sub == sub[::-1]: + cnt.append(sub) + return len(cnt) From 0c4e0011d50fdb736081842e6c6f54e394290155 Mon Sep 17 00:00:00 2001 From: hu6r1s Date: Thu, 11 Sep 2025 11:59:18 +0900 Subject: [PATCH 5/6] feat: Solve longest-common-subsequence problem --- longest-common-subsequence/hu6r1s.py | 15 +++++++++++++++ 1 file changed, 15 insertions(+) create mode 100644 longest-common-subsequence/hu6r1s.py diff --git a/longest-common-subsequence/hu6r1s.py b/longest-common-subsequence/hu6r1s.py new file mode 100644 index 000000000..77de1c6fa --- /dev/null +++ b/longest-common-subsequence/hu6r1s.py @@ -0,0 +1,15 @@ +class Solution: + """ + 문제의 힌트에서 DP를 활용하는 것을 확인 + """ + def longestCommonSubsequence(self, text1: str, text2: str) -> int: + dp = [[0] * (len(text2)+1) for _ in range(len(text1)+1)] + + for i in range(1, len(text1)+1): + for j in range(1, len(text2)+1): + if text1[i-1] == text2[j-1]: + dp[i][j] = dp[i-1][j-1] + 1 + else: + dp[i][j] = max(dp[i-1][j], dp[i][j-1]) + + return dp[-1][-1] From 9c22f9e34b2f86499eb690baf5198a3f987b6345 Mon Sep 17 00:00:00 2001 From: hu6r1s Date: Thu, 11 Sep 2025 12:18:36 +0900 Subject: [PATCH 6/6] feat: longest-repeating-character-replacement problem --- .../hu6r1s.py | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) create mode 100644 longest-repeating-character-replacement/hu6r1s.py diff --git a/longest-repeating-character-replacement/hu6r1s.py b/longest-repeating-character-replacement/hu6r1s.py new file mode 100644 index 000000000..d18f9af88 --- /dev/null +++ b/longest-repeating-character-replacement/hu6r1s.py @@ -0,0 +1,18 @@ +class Solution: + def characterReplacement(self, s: str, k: int) -> int: + counts = {} + left = 0 + max_count = 0 + res = 0 + + for right in range(len(s)): + counts[s[right]] = counts.get(s[right], 0) + 1 + max_count = max(max_count, counts[s[right]]) + + while (right - left + 1) - max_count > k: + counts[s[left]] -= 1 + left += 1 + + res = max(res, right - left + 1) + + return res