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1000 games of Craps stats (arrays)

brahe (1)
Hello, I am working on this program that plays a simple game of craps but plays it 1000 times. Then I have it show me how times the is won on the first roll, second roll, and so forth. I also have done this for lost games as well. Then I have it also telling me the calculated odds at winning craps every 100 games!

But I need the program now to tell me the average length of the games played in rolls! For example "Average length of the game of craps = ?? rolls". Seems easy enough, but when I did avg = sum / size its giving a higher value than what I should be expecting. I am getting around 14 rolls as an average when a more than half of the games won or lost are in the first roll of the game!

I am basically deriving all my stats from arrays and counters. And I am not asking for someone to write the code for me, but I am seriously just stuck on the average of an array and I don't know what else to do! I would really appreciate any tips or advice, thank you in advance.

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  #include "stdafx.h"
#include <iostream>
#include <cstdlib>
#include <ctime>
#include <iomanip>

using namespace std;

int rollDice();
int oddWin(int, int);

int _tmain(int argc, _TCHAR* argv[])
{

	cout << setprecision(2) << fixed;

	enum Status{CONTINUE, WON, LOST};

	int myPoint, gamesPlayed, sumOfDice, wsum = 0, lsum = 0, a = 0, i, k, l, m;
	
	double avg, avgSum = 0.0;

	const int rollFreq = 35;
	
	static int wcount = 0, lcount = 0, roll = 0;
	
	int wround[rollFreq] = { 0 };
	int lround[rollFreq] = { 0 };

	Status gameStatus;
	
	srand(time(0));

	for (gamesPlayed = 1; gamesPlayed <= 1000; gamesPlayed++)
	{
		roll++;
		sumOfDice = rollDice();
		switch (sumOfDice)
		{
		case 7:
		case 11:
			gameStatus = WON;
			wcount++;
			break;
		case 2:
		case 3:
		case 12:
			gameStatus = LOST;
			lcount++;
			break;
		default:
			gameStatus = CONTINUE;
			myPoint = sumOfDice;
			break;
		}

		while (gameStatus == CONTINUE)
		{
			sumOfDice = rollDice();
			roll++;
			if (sumOfDice == myPoint)
			{
				gameStatus = WON;
				wcount++;
			}
			else
			if (sumOfDice == 7)
			{
				gameStatus = LOST;
				lcount++;
			}
		}

		if (gameStatus == WON)
			wround[roll]++;

		if (gameStatus == LOST)
			lround[roll]++;

		roll = 0;
	}

	//WON GAMES
	cout << "\nWins:" << endl;

	for (k = 1; k < rollFreq - 15; k++)
		cout << wround[k] << setw(13) << " games won on " << k << " rolls" << endl;

	for (i = 20; i < rollFreq -1; i++)
		wsum += wround[i];
	cout << wround[i] << setw(13) << " games won on 20 or more rolls" << endl;
	
	//LOST GAMES
	cout << "\n\nLoses: " << endl;

	for (m = 1; m < rollFreq-15; m++)
		cout << lround[m] << setw(13) << " games lost on " << m << " rolls" << endl;

	for (l = 20; l < rollFreq -1; l++)
		lsum += lround[l];
	cout << lround[l] << setw(13) << " games lost on 20 or more rolls\n\n" << endl;

	//ODDS OF WINNING
	oddWin(wcount, gamesPlayed);

	//AVGWIN
        //IM STUCK HERE

	system("pause");
	return 0;
}

int rollDice()
{
	int die1 = 1 + rand() % 6;
	int die2 = 1 + rand() % 6;
	int sum = die1 + die2;

	return sum;
}

int oddWin(int x, int y)
{
	int c = 1000;
	double odds;

	for (; c > 0; c= c - 100)
	{
		odds = (x / (static_cast<double>(y / c)));
		odds = (odds / c) * 100;

		cout << "Odds of winning in " << c << " games = " << odds << "%" << endl;
	}

	return 0;
}


It's a little sloppy right now, but I am just trying to get the program to do what I need it to do.
ne555 (10692)
> but when I did avg = sum / size
I don't see that in your code.

> tell me the average length of the games played in rolls
you have arrays `wround' and `lround' that counts the length of won and lost games. As you don't care why it terminates you need to sum them
t_j = w_j + l_j
Those are counts, to translate them to relative frequencies you divide over the total amount of games played.
p_j = t_j/sum(t_j)
Then compute the expected value
E = sum j*p_j


Other things
> wround[roll]++;
`roll' may excede the size of the array, you'll be accessing out of bounds then.

> odds = (x / (static_cast<double>(y / c)));
It will first perform the integer division, and later convert it to double. So you already truncated the result.
No idea what you are trying to do there, `x' never changes inside the loop.
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