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LeetCode 153. Find Minimum in Rotated Sorted Array

Jun 29, 2025 · 4 min read · Question 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: [4,5,6,7,0,1,2] if it was rotated 4 times. [0,1,2,4,5,6,7] if it was rotated 7 times. No...

LeetCode 268: Missing Number

Jun 27, 2025 · 2 min read · class Solution { public: int missingNumber(vector<int>& nums) { int result = nums.size(); for (int i = 0; i < nums.size(); i++) { result ^= i ^ nums[i]; } return result; } }; Question Given an ar...

LeetCode 338: Counting Bits

Jun 26, 2025 · 2 min read · Problem Overview Given an integer n, return an array ans of length n + 1 where ans[i] is the number of set bits in the binary representation of i. Example: n = 5 → Output: [0, 1, 1, 2, 1, 2] Constraints: 0 <= n <= 10^5 Solution 1: Brute Force Thi...

LeetCode 191. Number of 1 Bits

Jun 12, 2025 · 2 min read · Problem Overview The goal is to write a function that takes an unsigned integer and returns the number of ‘1’ bits it has in its binary representation. This value is also known as Hamming weight. This is the classic bit manipulation problem. Solution...