How does the following program output 66???

Question

int main() {
int x = 24;
int y = 36;

//calling the function with both parameters
int result = sum(x, y);
cout << result << endl;
//Outputs 60

//calling the function without b
result = sum(x);
cout << result << endl;
//Outputs 66

Answer 1

int sum(int a, int b=42) {
int result = a + b;
return (result);
}
The default value of b is 42.
If you call the function without b then the second parameter will have the default value

Answer 2

default value of y parameter may be 20

Answer 3

can you explain it a bit??

Answer 4

If the corresponding argument is missing when you call a function, it uses the default value.And the default value was 42,so 24 + 42=66