Chapter 3, Problem 1P

Write a program to score the paper-rock-scissor game. Each of two users types in either P, R, or S. The program then announces the winner as well as the basis for determining the winner: Paper covers rock. Rock breaks scissors. Scissors cut paper, or Nobody wins. Be sure to allow the users to use lowercase as well as uppercase letters. Your program should include a loop that lets the user play again until the user says she or he is done.

Program Plan Intro

Program plan:

• Include necessary header files.
• Declare the namespace.
• Define the class “Player”.
  • Declare the necessary functions within the “public” access specifier.
  • Declare the necessary variables with the “private” access specifier.
  • The initializer sets “Player::totWins” to “0”.
  • Define the function “play()”.
    • Print the statement.
    • Get the input “choice” from the user.
    • Call the function “toupper()” and assign the result into the variable “choice”.
  • Define the function “Ch()”.
    • Return the value of the variable “choice”.
  • Define the function “AccWins()”.
    • Return the value of the variable “totWins”
  • Define the function “IncWins()”.
    • Increment the value of the variable “totWins” by “1”.
  • Declare the function “wins()”.
  • Define the function “wins()”.
    • The “if” loop check the expression.
      • True, user 1 wins by calling the function “IncWins()”.
      • Return “1”.
    • The “else if” loop check the expression.
      • True, user 2 wins by calling the function “IncWins()”.
      • Return “2”.
    • Otherwise, return zero.
• Define the “main()” function.
  • Create objects for the class “Player”.
  • Initialize the variable.
  • The “while” loop check the condition.
    • True, objects call the function “play()”.
    • Define the “switch” case.
      • Define “case 0” for no winner.
      • Define “case 1” for player 1 wins.
      • Define “case 2” for player 2 wins.
    • Call the function “toupper()” and assign the result in the variable “answer”.
  • Return “0”.

Program Description Answer

Program to score the paper-rock-scissor game.

Explanation of Solution

Program:

//Include necessary header files

#include <iostream>

#include <cctype>

//Declare the namespace

using namespace std;

//Define the class Player

class Player

{

//Access specifier

public:

  //Constructor, declare the function Player()

  Player();

  //Declare the function play()

  void play();

  //Declare the function Ch()    

  char Ch();

  //Declare the function AccumulatedWins     

  int AccWins();

  //Deeclare the function IncWins()

  void IncWins();

//Access specifier

private:

  //Variable declaration

  char choice;        

  int totWins; 

};

//Initializer sets Player::totWins to 0

Player::Player():totWins(0)

{

}

//Define the function play()

void Player::play()

{

  //Print the statement

  cout << "Please enter either R)Rock, P)Paper, or S)Scissor." << endl;

  //Get the input from the user

  cin >> choice;

  //Call the function toupper() and assign the result in choice

  choice = toupper(choice);

}

//Define the function Ch()

char Player::Ch()

{

  //Return the value of the variable choice

  return choice;

}

//Define the function AccWins()

int Player::AccWins()

{

  //Return the value of the variable totWins

  return totWins;

}

//Define the function IncWins()

void Player::IncWins()

{

  //Increment the value of the variable totWins by 1

  totWins++;

}

//Declare the function wins()

int wins(Player& user1, Player& user2);

//Define the function wins()

int wins(Player& user1, Player& user2 )

{

  //Check, the expression

  if( ( 'R' == user1.Ch() && 'S' == user2.Ch() )||

      ( 'P' == user1.Ch() && 'R' == user2.Ch() )||

      ( 'S' == user1.Ch() && 'P' == user2.Ch() )  )

  {

    //True, user 1 wins by calling the function IncWins()

    user1.IncWins();

    //Return 1

    return 1;

  }

  //Check, the expression

  else if( ( 'R' == user2.Ch() && 'S' == user1.Ch() )

       || ( 'P' == user2.Ch() && 'R' == user1.Ch() )

       || ( 'S' == user2.Ch() && 'P' == user1.Ch() ) )

  {

    //True, user 2 wins by calling the function IncWins()

    user2.IncWins();

    //Return 1

    return 2;

  }

  //Otherwise

  else

    //Return zero, no winner

    return 0;

}

//Define the main() function

int main()

{

  //Create objects for the class Player

  Player player1;

  Player player2;

  //Initialize the variable answer as Y

  char answer = 'Y';

  //Check, Y is equal to answer

  while ('Y' == answer)

  {

    //True, the objects call the function play()

    player1.play();

    player2.play();

    //Swich case

    switch( wins(player1, player2) )

    {

    //Case 0 for no winner

    case 0:

      //Print the result

      cout << "No winner. " << endl

           << "Totals to this move: " << endl

          << "Player 1: " << player1.AccWins()

          << endl

          << "Player 2: " << player2.AccWins()

          << endl

          << "Play again? Y/y continues other quits";

      //Get the input from the user

      cin >> answer;

      //Print the statement

      cout << "Thanks " << endl;

      //Break the statement

      break;

    //Case 1 for player 1 wins

    case 1:

      //Pint the result

      cout << "Player 1 wins." << endl

            << "Totals to this move: " << endl

            << "Player 1: " << player1.AccWins()

            << endl

            << "Player 2: " << player2.AccWins()

            << endl

            << "Play Again? Y/y continues, other quits. ";

      //Get the input from the user

      cin >> answer;

      //Print the statement

      cout << "Thanks " << endl;

      //Break the statement

      break;

    //Case 2 for player 2 wins

    case 2:

      //Pint the result

      cout << "Player 2 wins." << endl

           << "Totals to this move: " << endl

           << "Player 1: " << player1.AccWins()

           << endl

           << "Player 2: " << player2.AccWins()

           << endl

           << "Play Again? Y/y continues, other quits.";

      //Get the input from the user

      cin >> answer;

      //Print the statement

      cout << "Thanks " << endl;

      //Break the statement

      break;

    }

/*Call the function toupper() and assign the result in the variable answer*/

  answer = toupper(answer);

  }

  //Return zero

  return 0;

}

Sample Output

Output:

Please enter either R)Rock, P)Paper, or S)Scissor.

R

Please enter either R)Rock, P)Paper, or S)Scissor.

S

Player 1 wins.

Total to this move:

Player 1: 1

Player 2: 0

Play Again? Y/y continues, other quits. Y

Thanks

Please enter either R)Rock, P)Paper, or S)Scissor.

P

Please enter either R)Rock, P)Paper, or S)Scissor.

S

Player 2 wins.

Total to this move:

Player 1: 1

Player 2: 1

Play Again? Y/y continues, other quits. Y

Thanks

Please enter either R)Rock, P)Paper, or S)Scissor.

S

Please enter either R)Rock, P)Paper, or S)Scissor.

R

Player 2 wins.

Total to this move:

Player 1: 1

Player 2: 2

Play Again? Y/y continues, other quits. N

Thanks