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What will be the output of the program? class A { public A(int x){} } class B extends A { } public class test { public static void main (String args []) { A a = new B(); System.out.println("complete"); } }

It compiles and runs printing nothing
Compiles but fails at runtime
Compile Error
Prints "complete"

Correct Answer: Compile Error

Explanation:

No constructor has been defined for class B therefore it will make a call to the default constructor but since class B extends class A it will also call the Super() default constructor.

Since a constructor has been defined in class A java will no longer supply a default constructor for class A therefore when class B calls class A's default constructor it will result in a compile error.

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