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Given an array where every element appears twice except two elements that appear only once, find those two unique numbers. Approach 1: Frequency Counting with Index Mapping This method uses a temporary array to count occurrences by treating the original values as indices in the counting array. #include <stdio.h> int main() { int arr[ ...

Convert Array to List with asList The Arrays.asList method wraps an array into a fixed-size list, enabling collection-based operations like iteration or passing to methods expecting a List. Signature: public static <T> List<T> asList(T... a) Example: import java.util.Arrays; import java.util.List; public class ArrayConversion { ...

Given two sorted integer arrays nums1 and nums2 in non-decreasing order, with lengths m and n respectively, merge them into nums1 while maintaining sorted order. Implementation Code function merge(nums1, m, nums2, n) { let i = nums1.length - 1; m--; n--; while(n >= 0) { while(m >= 0 && nums1[m] > nums2[n ...

Array Algorithms Binary Search Fundamentals Binary search operates on sorted sequences with distinct elements. The algorithm halves the search space repeatedly until locating the target or exhausting the range. Critical Implementation Details: Midpoint Calculation: Use mid = lo + (hi - lo) // 2 instead of (lo + hi) // 2 to prevent integer ove ...

Bitwise Operators Binary Operatinos int output = 12 & 3; System.out.println(output); // Output: 0 // AND operation: both bits must be 1 to produce 1 output = 12 & 11; System.out.println(output); // Output: 8 output = 12 | 11; System.out.println(output); // Output: 15 // OR operation: at least one bit is 1 to produce 1 output = 12 ^ 1 ...

Arrays in Go represent fixed-length sequences of elements with the same type. Each element in an array is accessible by its index, and the total number of elements defines the array's length. Array Declaration Syntax Go provides several ways to declare arrays: var byteArray [32]byte // 32-element byte array var pointArray [1000]*floa ...