Traversing Arrays

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

◇Overview

Traversing an array means visiting each element sequentially, typically using a loop.

◇Key Concepts

for loop is the most common traversal method while and do-while can also traverse arrays Pointer arithmetic provides an alternative traversal 2D arrays require nested loops

◇Details / Theory

For Loop Traversal

int arr[5] = {10, 20, 30, 40, 50};
for (int i = 0; i < 5; i++) {
    printf("%d ", arr[i]);
}
// Output: 10 20 30 40 50

Pointer-Based Traversal

int arr[5] = {10, 20, 30, 40, 50};
int *p = arr;
for (int i = 0; i < 5; i++) {
    printf("%d ", *(p + i));
}

Traversal for Aggregation

int arr[5] = {10, 20, 30, 40, 50};
int sum = 0;
for (int i = 0; i < 5; i++) {
    sum += arr[i];
}
printf("Sum: %d\n", sum);  // Sum: 150

2D Array Traversal

int matrix[3][4];
for (int i = 0; i < 3; i++) {
    for (int j = 0; j < 4; j++) {
        printf("%d ", matrix[i][j]);
    }
    printf("\n");
}

Common Traversal Patterns

◇Common Pitfalls

Off-by-one errors: using <= instead of < in the loop condition. Forgetting to pass array size to functions — cannot compute it from a pointer. Modifying the loop variable inside the loop body.

◇Summary

TL;DR — Array traversal visits each element using loops or pointer arithmetic. for loops are most common. 2D arrays need nested loops. Always respect bounds to avoid undefined behavior.

◇Links

Related: ◇Accessing Elements — ◇Size — ◇Arrays and Pointers — ◇One-Dimensional Arrays (1D Arrays) — ◇Two-Dimensional Arrays (2D Arrays) Source / Reference:

◇References & Navigation

• Previous Topic: ◇Accessing Elements
• Next Topic: ◇Common Array Operations & Considerations
• Related Notes: ◇Accessing Elements, ◇Iterative Statements in C