Writing first C program - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to include the standard input-output header.

C

#include [1]

Drag options to blanks, or click blank then click option'

A<stdlib.h>

B<math.h>

C<stdio.h>

D<string.h>

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong header that doesn't provide printf.

Forgetting the angle brackets around the header name.

The <stdio.h> header is needed for input and output functions like printf.

2fill in blank

medium

Complete the code to start the main function.

C

int [1]() {

Drag options to blanks, or click blank then click option'

Astart

Brun

Cbegin

Dmain

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different function name instead of main.

Omitting the parentheses after the function name.

The main function is the entry point of a C program.

3fill in blank

hard

Fix the error in the printf statement to print Hello World.

C

printf([1]);

Drag options to blanks, or click blank then click option'

A"Hello World"

B'Hello World'

CHello World

DHello World;

Attempts:

3 left

💡 Hint

Common Mistakes

Using single quotes which are for single characters.

Not using any quotes causing a syntax error.

The string to print must be inside double quotes "" in C.

4fill in blank

hard

Fill the blank to correctly end the main function with a return statement.

C

    return [1];
}

Drag options to blanks, or click blank then click option'

A1

B0

Cmain

Dvoid

Attempts:

3 left

💡 Hint

Common Mistakes

Returning 1 which usually means an error.

Returning the function name or void which is invalid.

Returning 0 from main means the program ended successfully.

5fill in blank

hard

Fill all three blanks to complete the full Hello World program.

C

#include [1]

int [2]() {
    printf([3]);
    return 0;
}

Drag options to blanks, or click blank then click option'

A<stdio.h>

Bmain

C"Hello World"

Dvoid

Attempts:

3 left

💡 Hint

Common Mistakes

Missing the header include.

Wrong function name or missing parentheses.

Not quoting the string in printf.

This is the complete minimal C program that prints Hello World.