C++ The Return Keyword
Return Values
The void keyword, used in the previous examples, indicates that the
function should not return a value. If you
want the function to return a value, you can use a data type (such as int,
string, etc.) instead of void, and use the return
keyword inside the function:
Example
int myFunction(int x) {
return 5 + x;
}
int main() {
cout << myFunction(3);
return 0;
}
// Outputs 8 (5 + 3)
Try it Yourself »
return 5 + x;
}
int main() {
cout << myFunction(3);
return 0;
}
// Outputs 8 (5 + 3)
This example returns the sum of a function with two parameters:
Example
int myFunction(int x, int y) {
return x + y;
}
int main() {
cout << myFunction(5, 3);
return 0;
}
// Outputs 8 (5 + 3)
Try it Yourself »
return x + y;
}
int main() {
cout << myFunction(5, 3);
return 0;
}
// Outputs 8 (5 + 3)
You can also store the result in a variable:
Example
int myFunction(int x, int y) {
return x + y;
}
int main() {
int z = myFunction(5, 3);
cout << z;
return 0;
}
// Outputs 8 (5 + 3)
Try it Yourself »
return x + y;
}
int main() {
int z = myFunction(5, 3);
cout << z;
return 0;
}
// Outputs 8 (5 + 3)
Pratical Example
Here is a simple and fun "game example" using a function with return
to double a number five times:
Example
int doubleGame(int x) {
return x * 2;
}
int main() {
for (int i = 1; i <= 5; i++) {
cout << "Double of " << i << " is " << doubleGame(i) << endl;
}
return 0;
}
Try it Yourself »
return x * 2;
}
int main() {
for (int i = 1; i <= 5; i++) {
cout << "Double of " << i << " is " << doubleGame(i) << endl;
}
return 0;
}