Understanding #if #elif #endifWhat is the output of the code given below?#include <stdio.h>int main(){ #if(!5 >= 5) int a = 5; #elif -1 int a = 10; #else int a = 15; #endif printf("a = %d", a); return 0;}

The output of the code will be "a = 10".

Here's the step by step explanation:

1. The #if directive checks if the condition (!5 >= 5) is true. The '!' operator is a logical NOT operator, which means it inverts the truthiness of the operand. But in C, any non-zero value is considered as true. So, !5 will be false (0). Hence, the condition (!5 >= 5) will be false because 0 is not greater than or equal to 5. So, the code inside this #if block will not be executed.

2. Then, it goes to the #elif directive. The condition here is -1. In C, any non-zero value is considered as true. So, -1 is true. Therefore, the code inside this #elif block will be executed. The variable 'a' is assigned the value 10.

3. The #else block is ignored because the #elif condition was true.

4. Finally, it prints "a = 10" because 'a' was assigned the value 10 in the #elif block.