#include <stdio.h>

void swap_var(int a, int b){

  int c;
  c = a;
  a = b;
  b = c;

}

void swap_ptr(int *a, int *b){

  int c;
  c = *a;
  *a = *b;
  *b = c;
}

int main(){

  int a = 3;
  int b = 5;

  printf("a = %d, b = %d\n",a,b);
  
  swap_var(a,b);
  printf("After swap_var(a,b):\t a = %d, b = %d\n",a,b);
  
  swap_ptr(&a, &b);
  printf("After swap_ptr(&a,&b):\t a = %d, b = %d\n",a,b);
}