C | Variable Declaration and Scope | Question 4

#include <stdio.h>
extern int var = 0;
int main()
{
    var = 10;
    printf("%d ", var);
    return 0;
}

(A) 10
(B) Compiler Error: var is not defined
(C) 0

Answer: (A)
Explanation: If a variable is only declared and an initializer is also provided with that declaration, then the memory for that variable will be allocated i.e. that variable will be considered as defined.

Refer: Understanding “extern” keyword in C

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