Functions

Functions name reusable work and return values to the caller.

functions.cpp

#include <iostream>

int square(int value) {
    return value * value;
}

int main() {
    int side = ;
    int area = square(side);

    std::cout << "side=" << side << std::endl;
    std::cout << "area=" << area << std::endl;
    return 0;
}

#include <iostream>

int square(int value) {
    return value * value;
}

int main() {
    int side = ;
    int area = square(side);

    std::cout << "side=" << side << std::endl;
    std::cout << "area=" << area << std::endl;
    return 0;
}

#include <iostream>

int square(int value) {
    return value * value;
}

int main() {
    int side = ;
    int area = square(side);

    std::cout << "side=" << side << std::endl;
    std::cout << "area=" << area << std::endl;
    return 0;
}

function call A function call runs the named function and can use the returned value in another expression.