Can we use function on left side of an expression in C and C++?

In C, it might not be possible to have function names on left side of an expression, but it’s possible in C++.

#include<iostream>

using namespace std;

/* such a function will not be safe if x is non static variable of it */
int &fun()
{
   static int x; 
   return x;
}    

int main()
{
   fun() = 10;

   /* this line prints 10 on screen */
   printf(" %d ", fun());

   getchar();
   return 0;
}

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