#include <stdio.h>


void swap(void **x, void **y) {
  
  void *t = *x;
  *x = *y;
  *y = t;
}

void print_int_array(char* name, int* array, int size){

  int i;

  printf("%s:", name);
  for(i= 0; i<size; i++)
    printf(" %i", array[i]);
  printf("\n");
}

void print_float_array(char* name, float* array, int size){

  int i;

  printf("%s:", name);
  for(i= 0; i<size; i++)
    printf(" %f", array[i]);
  printf("\n");
}

int main(){
  

  int i= 1;
  int j= 2;

  int* pi;
  pi= &i;

  int* pj;
  pj= &j;

  printf("i: %i j: %i\n", *pi, *pj);

  swap((void*)&pi, (void*)&pj);

  printf("i: %i j: %i\n", *pi, *pj);

  int a[]= {1, 2, 3, 4};
  int b[]= {5, 6, 7, 8};
  
  int *pa;
  pa = &a[0]; 

  int *pb;
  pb = &b[0];
  
  print_int_array("a", pa, 4);
  print_int_array("b", pb, 4);

  swap((void*)&pa, (void*)&pb);

  print_int_array("a", pa, 4);
  print_int_array("b", pb, 4);

  float x[]= {1.0, 2.0, 3.0, 4.0};
  float y[]= {5.0, 6.0, 7.0, 8.0};
  
  float *px;
  px = &x[0]; 

  float *py;
  py = &y[0];
  
  print_float_array("x", px, 4);
  print_float_array("y", py, 4);

  swap((void*)&px, (void*)&py);

  print_float_array("x", px, 4);
  print_float_array("y", py, 4);
}