/*********************************************
* File: proj4.c
* Author: Jonathan Rivera
* Date: 4/29/07
* Section: 102
* Email: jriv1@umbc.edu
*
* This program calculates the results of a 
* hailstone sequence for integers and ranges
* of integers.
**********************************************/

void PrintGreeting (void);
char PrintMenu (void);
void DetermineOutput (char);
int HailstoneSequence (int);

#include <stdio.h>

#define MIN 1
#define MAX 9999

int main()
{
	char choice; /* User's menu choice */
	
	
	PrintGreeting();
	choice = PrintMenu();
	DetermineOutput(choice);
	
	return 0;
}



void PrintGreeting (void)
{
	printf("\nWelcome to Hailstone Sequences. This program\n");
	printf("takes an integer and:\n"); 
	printf("  a) cuts it in half if its odd or\n");
	printf("  b) multiplies it by 3 and adds 1 if even\n");
	printf("until the number reaches 1.\n\n");
}

char PrintMenu (void)
{
	char choice;
	char newline;
	
	printf("    I - view sequence for an Individual value\n");
	printf("    R - view sequences for a Range of values\n");
	printf("    H - view the sequences and a Histogram of a range\n");
	printf("    W - Write sequences and a histogram of a range to a file\n");
	printf("    Q - Quit\n");
	printf("Enter choice : ");
	scanf("%c", &choice);
	scanf("%c", &newline);
	
	return choice;
}

void DetermineOutput (char)
{
	int value;      /* Single value for hailstone operation */
	int firstRange; /* First number in the range of values */
	int lastRange;  /* Last number in the range of values */
	while (choice != 'Q' || choice != 'q')
	{
		switch (choice)
		{
			case 'i':
				printf("Please enter an integer between ");
				printf("%d and %d : ", MIN, MAX);
				scanf("%d", &value);
				HailstoneSequence(value);
				break;
			case 'I':
				printf("Please enter an integer between ");
				printf("%d and %d : ", MIN, MAX);
				scanf("%d", &value);
				HailstoneSequence(value);
				break;
			case 'r':
				printf("First number in the range :\n");
				printf("Please enter an integer between ");
				printf("%d and %d : ", MIN, MAX - 1);
				break;
		}
	}
}

int HailstoneSequence (int)
{
	int lengthOfSequence = 1;
	printf("%5d :%8d", int, int);
	
	while (int != 1)
	{
		if (int % 2 == 0)
		{
			int = int / 2;
		}
		elseif (int % 2 == 1)
		{
			int = (int * 3) + 1;
		}
		printf("%8d, int);
		lengthOfSequence++;
		
		if (lengthOfSequence % 9 == 0)
		{
			printf("\n       ");
		}
	}
	printf("\nlength of sequence = %d\n\n", lengthOfSequence);
	choice = PrintMenu();
	
	return lengthOfSequence;
}