// Trailing parameters can be given default values.
// This also works for methods.
// You can achieve the same effect through function overloading,
// but this can be more convenient.

#include <iostream>

using namespace std;

// This functions accepts one or two arguments.
void foo(int a, int b=4) {
    cout << "a=" << a << " b=" << b << '\n';
}

int main() {
    foo(1,2);		// Will print a=1 b=2
    foo(3);		// Will print a=3 b=4
    return 0;
}