Keeping track of used letters in hangman game

[nz881]

Hi am trying to make a hangman game in c++. Everything works so far but i can't seem to keep track of the used words in the game. As in,if a letter has already been entered before, the computer will have to display a message saying exactly that to the user,hence preventing them from using the same letter again.I have included the code below,please take a look at it and let me know how i can solve this issue.

#include<iostream>
#include<cstring>
#include<cstdlib>
#include<ctime>

using namespace std;

int main(){


  string words[] =
    {   "artistic",
        "recreational",
        "programmer",
        "indistinct",
        "sincere",
        "pulchritude",
        "legendary",
        "scientific",
        "oblivious",
        "tomorrow"
    };
   string word,unknownword,wordrevelation,playername,usedletters;
   int wordlength,numwrongofguesses,i,w,count;
   char letter,playagain;
   bool letterfound;

   cout << "Please enter your name: ";
   getline(cin,playername);
   cout << endl << endl;
   cout << "OKAY " << playername << " HERE WE GO!!!!!!!!!";
   cout << endl << endl;

    srand(time(0));
    w=rand()%10;
    word=words[w];

    wordrevelation=word;
    wordlength=word.size();

    for(i=0;i<wordlength;i++){
        unknownword[i]=word[i];
        word[i]='-';
    }
    cout << "OKAY HERES THE HIDDEN WORD "<< word << " AND IT IS " << wordlength << " LETTERS LONG" << endl << endl << endl;

    numwrongofguesses=8;
    count=0;
    bool Gameover=false;
    while(!Gameover){
        cout << "ENTER A LETTER " << playername << " : ";
        cin >> letter;
        
        

        letterfound=false;
        for(i=0;i<wordlength;i++){
            if(unknownword[i]==letter){
                letterfound=true;
                word[i]=letter;
                count++;
            }
        }
        cout << endl << endl;

        if(letterfound==true){
            word[i]=letter;
            cout << "THE LETTER " << letter << " EXISTS IN THE WORD" << endl << endl << endl;
            cout << "                              ";
            for(i=0;i<wordlength;i++){
                cout << word[i];
            }
            cout << endl << endl;
       }else{
             cout << "SORRY " << playername << ", " << letter << " DOES NOT EXIST IN THIS WORD" << endl << endl << endl;
             numwrongofguesses--;
            }

        if(numwrongofguesses==7){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << endl << endl;
        }else if(numwrongofguesses==6){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << "|                O" << endl;
            cout << endl << endl;
        }else if(numwrongofguesses==5){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << "|                O" << endl;
            cout << "|                X" << endl;
            cout << endl << endl;
        }else if(numwrongofguesses==4){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << "|                O" << endl;
            cout << "|               /X" << endl;
            cout << "|              /" << endl;
            cout << endl << endl;
        }else if(numwrongofguesses==3){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << "|                O" << endl;
            cout << "|               /X\\" << endl;
            cout << "|              /   \\" << endl;
            cout << endl << endl;
        }else if(numwrongofguesses==2){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << "|                O" << endl;
            cout << "|               /X\\" << endl;
            cout << "|              / | \\" << endl;
            cout << endl << endl;
        }else if(numwrongofguesses==1){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << "|                O" << endl;
            cout << "|               /X\\" << endl;
            cout << "|              / | \\" << endl;
            cout << "|               /" << endl;
            cout << "|              /" << endl;
            cout << endl << endl;
        }else if(numwrongofguesses==0){
            cout << "------------------" << endl;
            cout << "|                |" << endl;
            cout << "|                O" << endl;
            cout << "|               /X\\" << endl;
            cout << "|              / | \\" << endl;
            cout << "|               / \\" << endl;
            cout << "|              /   \\" << endl;
            cout << "|----------|" << endl;
            cout << "|----------|" << endl;
            cout << endl << endl;
            cout << "                " << playername << " YOU HAVE BEEN HANGED!!!!" << endl << endl << endl;
            cout << "               THE WORD WAS " << wordrevelation << endl << endl << endl;
            Gameover=true;
            break;
        }

        if(numwrongofguesses==7 || numwrongofguesses==6 || numwrongofguesses==5 ||
           numwrongofguesses==4 || numwrongofguesses==3 || numwrongofguesses==2 ||
           numwrongofguesses==1 || numwrongofguesses==0){
               cout << "                                ";
               for(i=0;i<wordlength;i++){
                cout << word[i];
            }
        }
        cout << endl << endl;

        if(count==wordlength){
            cout << "CONGRATULATIONS " << playername << "! YOU GUESSED THE WORD!!! IT'S " << wordrevelation << endl << endl << endl;
            Gameover=true;
            break;
        }

        if(Gameover){
            cout << playername << " THANKS FOR PLAYING.HOPE TO SEE YOU AGAIN.";
            break;
        }
    }



}

[48T7M4Gy]

One way is to replace the used letter by a zero or some other digit in the word. Or delete the letter from the word.

[JLBorges]

Maintain a set of available letters.

#include <iostream>
#include <string>
#include <set>
#include <cctype>

int main() {

    // ...

    static const std::string alphabet = "abcdefghijklmnopqrstuvwxyz" ; // #include <string>

    // #include <set> http://en.cppreference.com/w/cpp/container/set
    std::set<char> unused( alphabet.begin(), alphabet.end() ) ; // all letters are unused at the start

    bool Gameover=false;
    while(!Gameover){

        std::cout << "enter one of these letters [" ;
        for( char c : unused ) std::cout << c ;
        std::cout << "]: " ;

        char letter ;
        std::cin >> letter;
        letter = std::tolower(letter) ; // if uppercase, convert to lower case // #include <cctype>

        if( !std::isalpha(letter) ) { // if it is not a letter
            std::cout << "that is not a letter.\n" ;
        }


        else if( unused.find(letter) == unused.end() ) { // if this letter had been used earlier
            std::cout << "the letter " << letter << " was used earlier\n" ;
        }

        else {
            unused.erase(letter) ; // remove this letter from the set of unused letters

            bool letterfound=false;

            // rest of the code

        }
    }
}

[48T7M4Gy]

#include <iostream>
#include <stdio.h>

int main ()
{
    char ch;

    char letters[26];                    /// simple array to keep track
    for (int i =0; i < 26; i++ )
        letters[i] = '0';

    while(true)
    {
        std::cin >> ch;                 /// read in a letter
        letters[toupper(ch) - 65] = '1';/// sets letter as used

        for (int i = 0; i <26; i++)     /// just for show
            std::cout << letters[i];
        std::cout << std::endl;
    }
    return 0;
}