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You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them is that adjacent houses have security systems connected and it will automatically contact the police if two adjacent houses were broken into on the same night.

191. Number of 1 Bits

Posted on 2025-01-02 Edited on 2025-06-14 In Leetcode

191. Number of 1 Bits

Description

Given a positive integer n, write a function that returns the number of set bits in its binary representation (also known as the Hamming weight).

190. Reverse Bits

Posted on 2025-01-02 Edited on 2025-06-14 In Leetcode

190. Reverse Bits

Description

Reverse bits of a given 32 bits unsigned integer.

695. Max Area of Island

Posted on 2025-01-02 Edited on 2025-06-14 In Leetcode

695. Max Area of Island

Description

You are given an m x n binary matrix grid. An island is a group of 1‘s (representing land) connected 4-directionally (horizontal or vertical.) You may assume all four edges of the grid are surrounded by water.

684. Redundant Connection

Posted on 2025-01-02 Edited on 2025-06-14 In Leetcode

684. Redundant Connection

Description

In this problem, a tree is an undirected graph that is connected and has no cycles.

678. Valid Parenthesis String

Posted on 2024-12-30 Edited on 2025-06-14 In Leetcode

678. Valid Parenthesis String

Description

Given a string s containing only three types of characters: '(', ')' and '*', return true if s is valid .

153. Find Minimum in Rotated Sorted Array

Posted on 2024-12-30 Edited on 2025-06-14 In Leetcode

153. Find Minimum in Rotated Sorted Array

Description

Suppose an array of length n sorted in ascending order is rotated between 1 and n times. For example, the array nums = [0,1,2,4,5,6,7] might become: