#include <stdio.h>

void swap(int*, int*);
void swap2(int, int);

int main() { 
	int i = 5, j = 10;
	printf("before swap i = %d, j=%d\n", i, j);     // output: i=5,j=10
	swap( &i, &j);
	printf("after swap  i = %d, j=%d\n", i, j);     // output: i=10,j=5
	
	swap2( i, j);  
    printf("after swap2  i = %d, j=%d\n", i, j);     // output: i=10,j=5  not swapped
	return 0;
}

void swap(int *first, int *second) {
	int temp;
	temp = *first;
	*first = *second;
	*second = temp;
}

void swap2(int first, int second) {
	int temp;
	temp = first;
	first = second;
	second = temp;
}

/*
before swap i = 5, j=10
after swap  i = 10, j=5
after swap2  i = 10, j=5
*/