//
//  main.cpp
//  Runsofthrees
//
//  Created by Kevin Seppi on 10/7/16.
//  Copyright © 2016 Kevin Seppi. All rights reserved.
//
 
#include <iostream>
#include <iomanip>
#include <stdlib.h>
#include <time.h>
 
using namespace std;
 
int main(int argc, const char * argv[]) {
    const int MAX_FACE = 6;
    const int LOOKING_FOR = 3;
    const int NUMBER_OF_HUMAN_ROLLS = 10;
    const int NUMBER_OF_ROLLS = 100;
    const int NUMBER_OF_SIMULATIONS = 1000;
 
    int dieFace = 0;
    int currentRunLength = 0;
    int longestRunLength = 0;
    int totalLongestRunLength = 0;
    double averageLongestRunLength = 0;
 
    cout << fixed << setprecision(2);
    srand(static_cast <unsigned int>(time(0)));
    // try the following line instead and run the program twice!
    // srand(42); // Same sequence of random numbers every time (nothing special about 42, just a particular sequence)
 
 
    cout << "Count runs of: " << LOOKING_FOR << " in rolls of a die:" << endl;
    cout << "First you try being the random number generator, give me (all at once or one at a time) ";
    cout << NUMBER_OF_HUMAN_ROLLS << " int's in the range 1-6: ";
 
    for (unsigned int i = 0; i < NUMBER_OF_HUMAN_ROLLS; i++) {
        // Random roll of a 6 sided die
        cin >> dieFace;
 
        if (dieFace == LOOKING_FOR) {
            currentRunLength++;
            longestRunLength = max(longestRunLength, currentRunLength);
        }
        else {
            currentRunLength = 0;
        }
    }
    cout << endl;
    cout << "Summary:" << endl;
 
    cout << "The longest run of " << LOOKING_FOR << " was " << longestRunLength << endl;
    cout << endl;
 
    cout << "...interesting, now let's let the computer make random values:" << endl;
    cout << endl;
    cout << "Count runs of: " << LOOKING_FOR << " in rolls of a die:" << endl;
 
    currentRunLength = 0;
    longestRunLength = 0;
 
    cout << "Random values form a 6-sided die:" << endl;
    for (unsigned int i = 0; i < NUMBER_OF_ROLLS; i++) {
        // Random roll of a 6 sided die
        dieFace = rand() % MAX_FACE + 1;
        cout << dieFace << " ";
 
        if (dieFace == LOOKING_FOR) {
            currentRunLength++;
            longestRunLength = max(longestRunLength, currentRunLength);
        }
        else {
            currentRunLength = 0;
        }
    }
    cout << endl;
    cout << "Summary:" << endl;
 
    cout << "The longest run of " << LOOKING_FOR << " was " << longestRunLength << endl;
    cout << endl;
 
    cout << "...interesting, but what is the AVERAGE of the LONGEST runs over 1000 simulations?" << endl;
    cout << "Let's try it:" << endl;
    cout << endl;
    cout << "Simulating..." << endl;
    totalLongestRunLength = 0;
    for (unsigned int i = 0; i < NUMBER_OF_SIMULATIONS; i++) {
        currentRunLength = 0;
        longestRunLength = 0;
        for (unsigned int j = 0; j < NUMBER_OF_ROLLS; j++) {
            dieFace = rand() % MAX_FACE + 1;
 
            if (dieFace == LOOKING_FOR) {
                currentRunLength++;
                longestRunLength = max(longestRunLength, currentRunLength);
            }
            else {
                currentRunLength = 0;
            }
        }
        //cout << longestRunLength << endl;
        totalLongestRunLength += longestRunLength;
    }
    cout << endl;
    cout << "Summary:" << endl;
 
    averageLongestRunLength = totalLongestRunLength/(static_cast<double>(NUMBER_OF_SIMULATIONS));
 
    cout << "The average longest run of " << LOOKING_FOR << " was " << averageLongestRunLength << endl;
    cout << endl;
 
    system("pause");
    return 0;
}
cs-142/runs-in-random-numbers.txt · Last modified: 2016/10/07 18:35 by kseppi
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