Function parameters in C++ - Mini Project: Build & Apply

Function parameters

📖 Scenario: You are creating a simple calculator program that adds two numbers. You will learn how to use function parameters to pass values into a function.

🎯 Goal: Build a program that defines a function add which takes two numbers as parameters and returns their sum. Then call this function with specific numbers and print the result.

📋 What You'll Learn

Create a function named add that takes two int parameters named a and b

The function add should return the sum of a and b

Call the function add with the numbers 7 and 5

Print the result of the function call

💡 Why This Matters

🌍 Real World

Functions with parameters are used everywhere in programming to reuse code and perform tasks with different inputs, like calculators, games, and apps.

💼 Career

Understanding function parameters is essential for writing clean, reusable code, a key skill for any software developer.

1

Create the add function with parameters

Write a function named add that takes two int parameters called a and b. The function should return an int. Do not write the function body yet.

C++

// Your code here

Need a hint?

Start by writing the function header int add(int a, int b); and a main function.

2

Implement the add function to return the sum

Complete the add function so it returns the sum of the parameters a and b.

C++

int add(int a, int b);

int main() {
    return 0;
}

int add(int a, int b) {
    // Your code here
}

Need a hint?

Use the return statement to send back the sum of a and b.

3

Call the add function with 7 and 5

Inside the main function, call the add function with the arguments 7 and 5. Store the result in an int variable named result.

C++

int add(int a, int b);

int main() {
    // Your code here
    return 0;
}

int add(int a, int b) {
    return a + b;
}

Need a hint?

Use int result = add(7, 5); inside main to call the function and save the sum.

4

Print the result

Add a std::cout statement inside main to print the value of result. Include #include <iostream> at the top of the program.

C++

#include 

int add(int a, int b);

int main() {
    int result = add(7, 5);
    // Your code here
    return 0;
}

int add(int a, int b) {
    return a + b;
}

Need a hint?

Use std::cout << result << std::endl; to print the sum.