#include <stdio.h>
#include <math.h>
	/*initilize pointed values into 0*/
	int c5=0;
	int c2=0;
	int c1=0;
	int a_paid=1;
	int a_due=1;
	int dollars;
	int change;

/*assiging initialize value to the pointers*/
	paid=&a_paid;
	due=&a_due;	
/*function initialization*/
int getData(int *paid,int *due);
/*function initialization*/
void dispense(int change,int *dollars,int *c50,int *c20,int *c10);

int main()

{

	/*repeat the loop until user enters both 0*/
do {
	/*prompt user to enter 2 numbers*/
	getData (&paid,&due);
/*while the pointed values a_due(pointed by *due) and a_paid(pointed by *paid) not equals to 0 then do*/
while (&due!=0 && &paid!=0){
	/*calculate the change and the number of the respected pointers(cents)*/
	dispense (&a_paid,&a_due);

	printf ("\namount due:%d",due);
	printf ("amount paid:%d",paid);
	printf ("and thus change=%d",dollars);

	/*display specific output to user depending if the pointed values(cents) are 0*/
	if (change<5)	{
 	if (c2==0)	{
  printf ("You are suggested to give him/her %d 10-cents coin(s)",c1);}
 	if (c1==0)	{
  printf ("You are suggested to give him/her %d 20-cents coin(s)",c2);}
 	else
  printf ("You are suggested to give him/her %d 10-cents coin(s) %d 20-cents coin(s)",c1,c2);}

	else if (change>5)	{
 	if (c2==0)	{
  printf ("You are suggested to give him/her %d 10-cents coin(s) %d 50-cents coin(s)",c1,c5);}
 	if (c1==0)	{
  printf ("You are suggested to give him/her %d 20-cents coin(s) %d 50-cents coin(s) ",c2,c5);}
 	else
  printf ("You are suggested to give him/her %d 10-cents coin(s) %d 20-cents coin(s) %d 50-cents coin(s)",c1,c2,c5);}	

	else if (change==5) {
  printf ("You are suggested to give him/her %d 50-cents coin(s)",c5);}
  }
  } while (getData (&paid,&due)==1);
 	}

int getData (int *paid,int *due){


 printf ("\nThe amount-paid and amount-due should be entered in cents(integer)");
 /*repeat until due<0 or paid<due*/
 do {
 	printf ("\nTo terimate the program,enter 0 for both values.");
 	printf ("\nEnter the amount-paid abd amount-due please:");
 	scanf ("%d %d",&a_paid,&a_due);	} while (*due<0||*paid<*due);

 	if (*paid==0&&*due==0){
  return 0;}
 	else {
  return 1;}
}

void dispense (int change,int *dollars,int *c50,int *c20,int *c10){

/*By substract the paid and due and divide it by 10 to obtain the actual change,and round it up to the nearest 10*/
	change=(*paid-*due);
	dollars=&change;
       rounded=round(change);
	/*while the change is in range do the followings*/
	while (change>=10&&change<=90) {
 switch (rounded){
 case '10':c1+=1;
         break;
   
 case '20':c2+=1;
     break;

 case '30':c1+=1;
   c2+=1;
   break;

 case '40':c2+=2;
   break;

 case '50':c5+=1;
   break;

 case '60':c1+=1;
   c5+=1;
   break;

 case '70':c2+=1;
   c5+=1;
   break;

 case '80':c1+=1;
   c2+=1;
   c5+=1;
   break;

 case '90':c2+=2;
   c5+=1;
   break;

 default:printf ("\nCheck your input!");
 	printf("\nEnter the amount paid and amount-due please:"); }
	}
}