Manipulating Variable Given to Void Function in C

Question

Is there a way to implement that sort of Code

#include<stdio.h>

void func(int a)
{
    a++;
}

int main()
{
    int a=0;

    func(a);

    printf("%d", a);

    return 0;
}

The changes I have made to the variable a dont seem to carry over when I reuse it in the main function. I think its done by using static variables but i cant figure out how to do it

Answer 1

you need a 'c style pass by reference'

void func(int *a)
{
    (*a)++;
}

and

func(&a);

ie - pass in the address of 'a' as a pointer, then update it by dereferencing the pointer

Answer 2

If a is passed by copy (like in this case), changes made by your functions will not affect the variable in your main . You should pass this parameter by reference.

So the solution must be like the following one

#include<stdio.h>

void func(int* a) {
    (*a)++;
}

int main()
{
    int a=0;
    func(&a);
    printf("%d", a);
    return 0;
}