Array traversal in C - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does array traversal mean in C programming?

Array traversal means visiting each element of an array one by one, usually using a loop, to read or modify its values.

beginner

Which loop is commonly used for array traversal in C?

The for loop is commonly used because it allows easy control of the index from 0 to the array size minus one.

beginner

What is the starting index of an array in C?

The starting index of an array in C is 0, meaning the first element is accessed with index 0.

beginner

Show a simple C code snippet to print all elements of an integer array named arr of size n.

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

beginner

Why is it important to use the correct array size when traversing an array?

Using the correct size prevents accessing memory outside the array, which can cause errors or crashes.

What is the first index used when traversing an array in C?

A -1

B 1

C 0

D Array size

Arrays in C start at index 0, so traversal begins at 0.

Which loop is best suited for traversing an array when the size is known?

A for loop

B do-while loop

C while loop

D switch statement

The for loop is ideal for known sizes because it controls the index easily.

What happens if you traverse beyond the array size in C?

A Undefined behavior, possible crash or wrong data

B Array automatically resizes

C Compiler error

D Program safely ignores extra elements

Accessing outside array bounds causes undefined behavior and can crash the program.

How do you access the third element of an array named arr?

A arr[3]

B arr[2]

C arr[1]

D arr[0]

Since indexing starts at 0, the third element is at index 2.

Which of these is a correct way to traverse an array of size n?

A for (int i = n; i > 0; i--)

B for (int i = 1; i <= n; i++)

C for (int i = 0; i <= n; i++)

D for (int i = 0; i < n; i++)

Looping from 0 to less than n covers all valid indices.

Explain how to traverse an array in C and why the starting index is important.

Think about how arrays are indexed and how loops help visit each element.

Describe what could happen if you try to access an array element outside its size during traversal.

Consider what happens when you read memory not allocated for the array.