#include <iostream>
 
void foo(int a, int b, int c = -1) {
	std::cout << "foo(" << a << ", " << b << ", " << c << ")\n";
}
 
int main() {
	foo(1, 2);   // output: foo(1, 2, -1)
 
	// error: does not use default from surrounding scope
	//void foo(int a, int b = 0, int c);
 
	void foo(int a, int b, int c = 30);
	foo(1, 2);   // output: foo(1, 2, 30) 
 
	// error: we cannot redefine the argument in the same scope
	// void foo(int a, int b, int c = 35);
 
	// has a default argument for c from a previous declaration
	void foo(int a, int b = 20, int c);
	foo(1);      // output: foo(1, 20, 30)
 
	void foo(int a = 10, int b, int c);
	foo();       // output: foo(10, 20, 30)
 
	{
		// in inner scopes we can completely redefine them
		void foo(int a, int b = 4, int c = 8);
		foo(2);  // output: foo(2, 4, 8)
	}
 
	return 0;
}

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