/*
 * -----------------------------------------------------
 * CS2S03/SE2S03, September 2011
 * Assignment 2, Question 3
 * File: PE0302.cpp
 * -----------------------------------------------------
 * This program simulates flipping a coin repeatedly and 
 * continues until three consecutive heads are tossed.
 * -----------------------------------------------------
 */

#include "genlib.h"
#include "simpio.h"
#include "random.h"
#include <iostream>

const int NUM_CONSECUTIVE_HEADS = 3;

/* two sides of a coin */
enum sideT {
    head,
    tail
};

/* Private function prototypes */
sideT FlipCoin();

int main() {
    int nConsecutiveHeads = 0;
    int nTrials = 0;
	
    Randomize();

    while (nConsecutiveHeads != NUM_CONSECUTIVE_HEADS) {
        nTrials++;
        if (FlipCoin() == head) {
            cout << "heads" << endl;
            nConsecutiveHeads++;
        } else {
            cout << "tails" << endl;
            nConsecutiveHeads = 0;     // reset
        }
    }
			
    cout << "It took " << nTrials << " flips to get ";
    cout << NUM_CONSECUTIVE_HEADS << " consecutive heads." << endl;

    return 0;
}


/*
 * Function: FlipCoin()
 * Usage: side = FlipCoin();
 * -------------------------------------------------------------------
 * 
 * This function simulates flipping a coin. It returns head or tail 50
 * percent of the time.
 *
 * -------------------------------------------------------------------
 */


sideT FlipCoin() {
    return (RandomChance(0.50))? head : tail;
}