- Default arguments:
void greet(std::string name = "Guest") - Overloading: functions with the same name but different parameter types.
- Pass by reference with
&to change the caller's variable or avoid copying:void bump(int& n). - Use
const&for large read-only arguments:void print(const std::string& s). - Lambdas:
auto add = [](int a, int b) { return a + b; };
C++ Functions
Overloading, default arguments and recursion.
✍️ 2 exercises in this lessonKey Takeaways: C++ Functions
Mastering C++ Functions helps you write clean and reliable C++ code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
C++ Functions Code Example
C++#include <iostream>
#include <string>
int area(int side) { return side * side; }
double area(double r) { return 3.14159 * r * r; }
void greet(const std::string& name = "Guest") {
std::cout << "Hello, " << name << "\n";
}
void bump(int& n) { n += 10; }
int main() {
std::cout << area(4) << " " << area(1.0) << "\n";
greet();
greet("Bilal");
int score = 5;
bump(score);
std::cout << score << "\n";
auto multiply = [](int a, int b) { return a * b; };
std::cout << multiply(6, 7) << "\n";
return 0;
}Output
16 3.14159 Hello, Guest Hello, Bilal 15 42
Run this example on your own computer. The "Get Started" lesson shows how to set it up.
C++ Functions Practice Exercises
Check what you learned in “C++ Functions”.
/ 2 solved
Fill in the blank
Pass by reference so the function can change the caller's variable.
void bump(int n) { n += 10; }
✓ Correct!
Not quite. Try again.
Multiple choice
What is a lambda in C++?
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