Need help modifying this program

[deathslice]

Well I'm currently attempting attempting some of the beginners exercises from this link http://www.cplusplus.com/forum/articles/12974/ and the one I'm stuck at the moment is the bracket searching where I have to do the reverse and have the computer guess my number. The problem that I'm having is that I don't know much of my code I would have to modify to achieve that result nor do I know how I would go about doing that. Some general pointers would be nice.

  #include <iostream>
#include <ctime>
#include <limits>
#include <random>

using namespace std;

enum difficulty {EASY,NORMAL,HARD} settings;

int generator1()
{
    mt19937 randomGenerator(time(NULL));
    uniform_int_distribution<int> randomNumber(1,10);
    return randomNumber(randomGenerator);
}

int generator2()
{
    mt19937 randomGenerator(time(NULL));
    uniform_int_distribution<int> randomNumber(1,100);
    return randomNumber(randomGenerator);
}

int generator3()
{
    mt19937 randomGenerator(time(NULL));
    uniform_int_distribution<int> randomNumber(1,1000);
    return randomNumber(randomGenerator);
}

int main()
{
    int guessNumber, correctNumber = 0, guessCount = 0, guessLimit = 0;
    string gameDifficulty;

    cout << "Welcome to my guessing game program. Let's us begin. \n";
    cout << "\nPress any button to continue... ";
    cout << endl;
    cin.get();

    cout << "                    ---------------------------------";
    cout << "\nSettings available: |EASY\tNORMAL\t\tHARD|" << endl;
    cout << "                    ---------------------------------";

    cout << endl;

    cout << "                 -----------------------------------------------------";
    cout << "\nGuessing limit:  | Easy:5 Guesses  Normal:25 Guesses  Hard:50 Guesses| " << endl;
    cout << "                 -----------------------------------------------------";

    cout << "\n\nPlease enter the difficulty that you would like. ";
    getline(cin, gameDifficulty, '\n');

    cout << endl;

    while(gameDifficulty != "EASY" && gameDifficulty != "NORMAL" &&
          gameDifficulty != "HARD" && gameDifficulty != "easy" &&
          gameDifficulty != "normal" && gameDifficulty != "hard")
    {
        cerr << "This setting is nonsense. Pick a real setting. ";
        cin >> gameDifficulty;
        cin.ignore(numeric_limits<streamsize>::max(), '\n');
    }

    if(gameDifficulty == "EASY" || gameDifficulty == "easy")
    {
        guessLimit = 5;
        settings = EASY;
    }
    else if(gameDifficulty == "NORMAL" || gameDifficulty == "normal")
    {
        guessLimit = 25;
        settings =  NORMAL;
    }
    else if(gameDifficulty == "HARD" || gameDifficulty == "hard")
    {
        guessLimit = 50;
        settings = HARD;
    }

    switch(settings)
    {
    case 0:
        correctNumber = generator1();
        break;
    case 1:
        correctNumber = generator2();
        break;
    case 2:
        correctNumber = generator3();
    }
    cout << "\nGuess What number I'm thinking. ";
    cin >> guessNumber;

    do
    {
        while(!(cin))
        {
            cerr << "\nIncorrect input. Please try again. ";
            cin.clear();
            cin.ignore(numeric_limits<streamsize>::max(), '\n');
            cin >> guessNumber;
        }
        if(guessNumber < 0)
        {
            cerr << "\nThe number that you entered is negative.";
            cerr << " Please enter a positive number to \ncontinue. ";
            cin.ignore(numeric_limits<streamsize>::max(), '\n');
            cin >> guessNumber;
        }
    }
    while(guessNumber < 0);

    cout << endl;


    while(guessNumber != correctNumber && guessCount < guessLimit)
    {
        cout << "\nSorry, no cigar. ";
        cin >> guessNumber;
        guessCount++;
    }

    if(guessNumber == correctNumber)
    {
        cout << "\nCongratulations, you guessed the right number. ";
        cout << "\n\nIt only took " << guessCount << " guesses to guess ";
        cout << "the correct number. " << endl;
    }
    else
        cout << "\nBetter luck next time sucker. " << endl;

}

[minomic]

Hi, since you are a beginner, maybe it's useful to look at some examples before trying to write your own programs. Here's an example I just wrote:

#include <iostream>

using namespace std;

int guess(int min, int max) {
	return (max + min) / 2;
}

int main() {

	int count = 0;

	cout << "NUMBER GUESSING" << endl << endl;

	cout << "Insert minimum value: ";
	int min_val;
	cin >> min_val;

	int max_val;
	do {
		cout << "Insert maximum value: ";
		cin >> max_val;
	} while (max_val < min_val);

	cout << "Pick a number from " << min_val << " to " << max_val << "..." << endl;

	char ans = 0;
	int guessed_number = 0;

	do {
		guessed_number = guess(min_val, max_val);
		++count;

		cout << endl << "Is your number " << guessed_number << "?" << endl
				<< "Yes (Y) - No, it's bigger (B) - No, it's smaller (S) ";
		cin >> ans;

		if (ans == 'b' || ans == 'B') {
			min_val = guessed_number;
		}
		else if (ans == 's' || ans == 'S') {
			max_val = guessed_number;
		}
	} while (ans != 'y' && ans != 'Y');

	cout << endl << "So your number was " << guessed_number << " and it took me "
                << count << " attempts to find it."
			<< endl;
        return 0;
}

If there is something you don't understand, feel free to ask!

[deathslice]

Based on your example, I think I now understand the general structure on how want my code to look like. Thanks for your example.

[minomic]

You're welcome!

[deathslice]

Hey Minomic, so this what I was able to come up with and the computer was able to guess it 3 tries(was probably luck). Tell if there is any way I can make it more efficient.

#include <iostream>
#include <ctime>
#include <cstdlib>
#include <limits>

using namespace std;

int binarySearch(int);

int main()
{
    srand(time(NULL));

    int value;

    cout << "Enter a number from 1-100 and I will guess your number! ";
    cin >> value;

    while(value > 100)
    {
        cin.ignore(numeric_limits<streamsize>::max(), '\n');
        cerr << "\nThis value is too big. Only values 1 to 100 are accepted. ";
        cin >> value;
    }

    do
    {
        while(!(cin))
        {
            cerr << "\nIncorrect input. Please try again. ";
            cin.clear();
            cin.ignore(numeric_limits<streamsize>::max(), '\n');
            cin >> value;
        }
        if(value < 0)
        {
            cerr << "\nThe number that you entered is negative or past 100.";
            cerr << "\n\nPlease enter a positive number or something smaller to continue. ";
            cin.ignore(numeric_limits<streamsize>::max(), '\n');
            cin >> value;
        }
    }
    while(value < 0);


    cout << binarySearch(value);

    cout << endl;

    return 0;
}

int binarySearch(int value)
{
    int counter = 0;
    char response;

    int first = 0;
    int last = rand()%100+1;

    int middle = (first+last)/2;

    cout << "\nIs this your number " << middle << "? ";
    cin >> response;

    while(toupper(response) != 'Y' && toupper(response) != 'N')
    {
        cout << "Only Y,y,N or n are valid responses. ";
        cin >> response;
    }

    while(middle != value && counter < 7)
    {
        if(toupper(response) == 'Y')
        {
            break;
        }
        else if(middle < value && value - middle <= 5)
        {
            middle += 1;
        }
        else if(middle < value && value - middle <= 15)
        {
            middle += 5;
        }
        else if(middle < value)
        {
            middle += 25;
        }
        else if(middle > value && middle - value <= 5)
        {
            middle -= 1;
        }
        else if(middle > value && middle - value <= 15)
        {
            middle -= 5;
        }
        else if(middle > value)
        {
            middle -= 25;
        }
        else
            cout << "\nInvalid response. Try again";

        counter++;

        cout << "\nHow about this number: " << middle << "? ";
        cin >> response;

        while(toupper(response) != 'Y' && toupper(response) != 'N')
        {
            cout << "Only Y,y,N or n are valid responses. ";
            cin >> response;
        }
    }

    if(middle == value)
    {
        cout << "\n\nSo your number was " << middle << " and it only took me ";
        cout << counter << " tries. ";

        return value;
    }
    else
        cout << "\n\nI couldn't guess your number. ";

    return -1;
}

[deathslice]

I think I optimized it pretty well. Time to tackle the tic-tac-toe beginner exercise.

[deathslice]

Oh and if anybody finds any errors that I might have missed, please respond.

[minomic]

Ehm... Maybe I'm wrong but to me this seems like "cheating"! :)

You ask the user for the solution (i.e. the number he picked) but according to me you shouldn't. If you look at my code, I never ask the user for the solution: I just tell him to think about a number. Nevertheless, the program is still able to guess it. The reason is simple: at every iteration I split the possible range of values in two, so after an appropriate number of iterations I am able to track down the mysterious number...

The way you are doing is "suspect", because the solution is passed as a parameter do the binarySearch function. This means that the solution is actually used to find... the solution! And this doesn't make much sense, right? ;)