This is called default parameter, in which you set a default value for the variables. Suppose you call the function above as follows,
f(1,2), then it will take x=1 and y=2;
f(1), then it will take x=1 and automatically assign the default value to y , i.e y = 10.
So, in case you are not passing any value for that, the default value comes in action.
void point(int x = 3, int y = 4);
point(1,2); // calls point(1,2)
point(1); // calls point(1,4)
point(); // calls point(3,4)
Hope it helped. Do let me know if there is any confusion. Thank You for asking questions.
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