C++ | References | Question 4

Predict the output of following C++ program.

#include<iostream> 
using namespace std; 
  
int &fun() 
{ 
    static int x = 10; 
    return x; 
} 
int main() 
{ 
    fun() = 30; 
    cout << fun(); 
    return 0; 
} 

(A) Compiler Error: Function cannot be used as lvalue
(B) 10
(C) 30

Answer: (C)

Explanation: When a function returns by reference, it can be used as lvalue. Since x is a static variable, it is shared among function calls and the initialization line “static int x = 10;” is executed only once.
The function call fun() = 30, modifies x to 30. The next call “cout << fun()" returns the modified value.

Quiz of this Question

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes

Recommended Posts: