Function definition inside another function definition: is it valid?

Question

see this code

#include

int main()
{
    void test(void)
    {
        printf(\"test\");
        return;
    }
printf(\"main\");
return 0;
}
<         


        

Answer 1

Yes we can define a function in other function. I have compiled below written lines in gcc and it ran successfully without showing an error.

#include;
void main()
{
    int sum()
    {
        int a=30, b=10, c=20, sum=0;
        sum=a+b+c;
        return sum;
    }
    int a;
    a=sum();
    printf("Sum = %d", a);
}

O/p:60