Check out example codes for "how to use a pointer as a parameter in c". It will help you in understanding the concepts better.

Code Example 1

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
void add(int* a, int* b, int* c)
{
    *c = *a + *b;
}
int main()
{
	int a, b, c;
	a = 3;
	b = 5;
	add(&a, &b, &c);
	printf("%d", c);
}

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