C++ | Static Keyword | Question 1

Predict the output of following C++ program.

#include <iostream>
using namespace std;

class Test
{
    static int x;
public:
    Test() { x++; }
    static int getX() {return x;}
};

int Test::x = 0;

int main()
{
    cout << Test::getX() << " ";
    Test t[5];
    cout << Test::getX();
}

(A) 0 0
(B) 5 5
(C) 0 5
(D) Compiler Error

Answer: (C)
Explanation: Static functions can be called without any object. So the call “Test::getX()” is fine.

Since x is initialized as 0, the first call to getX() returns 0. Note the statement x++ in constructor. When an array of 5 objects is created, the constructor is called 5 times. So x is incremented to 5 before the next call to getX().
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