Common Array Operations & Considerations

Tags: #◇CCPROG2 #◇C Programming #◇Programming #◇Computer Science #◇Data Structures #◇Data Types #◇Structured Programming #◇Memory Management

◇Overview

Searching: Linear Search, Binary Search (if sorted)

◇Key Concepts

Searching Sorting Insertion/Deletion Size Calculation Assignment

◇Details / Theory

Searching: Linear Search, Binary Search (if sorted) Sorting: Bubble Sort, Selection Sort, Merge Sort, Quick Sort Insertion/Deletion: In static arrays, this requires shifting elements Size Calculation:

int size = sizeof(array) / sizeof(array[0]);

Only valid in the scope where the array is defined
Assignment:

int a[3] = {1,2,3};
int b[3];
for (int i = 0; i < 3; i++) b[i] = a[i];

◇Common Pitfalls

Using sizeof(arr) inside a function to calculate array size — it returns the pointer size instead; pass the size as a separate parameter Assigning arrays directly (b = a) — C does not support array assignment; use a loop or memcpy() to copy elements Inserting/deleting in the middle without shifting — you must manually shift subsequent elements, which is $O(n)$ Forgetting to check bounds before accessing or modifying elements — out-of-bounds access is undefined behavior

◇Summary

TL;DR — Common array operations: searching (linear/binary), sorting (bubble/selection/insertion), insertion/deletion (requires shifting, $O(n)$), size calculation (sizeof(arr)/sizeof(arr[0]) in declaring scope only), and element-wise copying (loop or memcpy, not direct assignment).

◇Links

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◇References & Navigation

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• Related Notes: ◇Traversing Arrays, ◇Arrays and Functions