Consider the following swap method. If String x = "Hello" and String y = "Goodbye", then swap(x, y); results in which of the following?
public void swap(String a, String b){
String temp;
temp = a;
a = b;
b = temp;
}
a) x is now "Goodbye" and y is now "Hello"
b) x is now "Goodbye" and y is still "Goodbye", but (x != y)
c) x is still "Hello" and y is now "Hello", but (x != y)
d) x and y are now aliases
e) x and y remain unchanged
Answer: e.
Explanation: When x and y are passed to swap, a and x become aliases and b and y become aliases. The statement temp = a sets temp to be an alias of a and x. The statement a = b sets a to be an alias of b and y, but does not alter x or temp. Finally, b = temp sets b to be an alias of temp and y, but does not alter y. Therefore, x and y remain the same.
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