#include <stdio.h>
#include <stdlib.h>

int main(void)
{
        int amount;        /* how much change the user has */
        int leftover;      /* used to hold amount as it decreases */
        int numquarters;   /* how many quarters */
        int numdimes;      /* how many dimes */
        int numnickels;    /* how many nickels */
        int numpennies;    /* how many pennies */
	int retval = 0;	/* return value of scanf */


        /* read in the amount and save it */
        printf("Enter amount of change: ");
	while(retval != 1){
		retval = scanf("%d", &amount);
       		 if (retval == EOF){
			printf("\n");
			exit(0);
		}
       		 if (amount < 0){
			fprintf(stderr, "Please enter a non-negative integer\n");
		}
	}

	leftover = amount;

        /* computer the number of quarters and how much is left over */
        numquarters = leftover / 25;
        leftover = leftover % 25;


        /* computer the number of dimes and how much is left over */
        numdimes = leftover / 10;
        leftover = leftover % 10;


        /* computer the number of nickels and how much is left over */
        numnickels = leftover / 5;
        leftover = leftover % 5;


        /* whatever is left over is the number of pennies */
        numpennies = leftover;


        /* print the result */
        printf("%d cents is %d quarters, %d dimes, %d nickels, and %d pennies\n",
                                amount, numquarters, numdimes, numnickels, numpennies);


        /* thank you, and goodnight! */
        exit(0);
}