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Random Number Generator issues

goldyn (24)
It seems as though my program is working great but I'm having problems with my random number generator. It keeps giving me a return value from the computer of scissors (or 3) for the computers random choice. What can I do?

Thanks,
goldyn
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//Type of Assignment: Homework Assignment 5
//Problem Number: 5
//Section Number: 100
//Author: Nate Kimpler
//Date Assigned: 10/18/2014
//Program Name: Assignment5
//File Name: Assignment5.cpp
//Time Spent on Program: 

//Purpose of Program: This program is meant to
//prompt the user to choose between 4 menu options.
// Each option will be the users choice of rock, paper, or scissors.
// the computer will then randomly generate a number and pit you against the computer




#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;

void user(int getUserChoice);
void comp(int getComputerChoice);
void winner(int UserChoice, int ComputerChoice);
	

int main()
{
int getComputerChoice = rand() % 3 + 1; //generates random number out of 3
int getUserChoice;


	do
	{
		cout << "Game Menu" << endl;
		cout << "---------" << endl;
		cout << "1) Rock" << endl;
		cout << "2) Paper" << endl;
		cout << "3) Scissors" << endl;
		cout << "4) Quit Program" << endl;
		cout << "Enter your choice(1-4)" << endl;
		cout << endl;
		cin >> getUserChoice; //takes user choice

		//validates menu selection
		while (getUserChoice < 1 || getUserChoice > 4)
		{
			cout << "That was not an option. Please enter a valid choice from the menu: ";
			cin >> getUserChoice;
			cout << endl;
		}
	user(getUserChoice);
	comp(getComputerChoice);
	winner(getUserChoice, getComputerChoice);

	}
	while (getUserChoice != 4);
	
		return 0;
	
}

void user(int getUserChoice)
{
	if (getUserChoice == 1)
		cout << "You picked Rock." << endl;
	else if (getUserChoice == 2)
		cout << "You picked Paper." << endl;
	else if (getUserChoice == 3)
		cout << "You picked Scissors." << endl;
	else if (getUserChoice == 4)
		return;
}
void comp(int getComputerChoice)
{
	if (getComputerChoice == 1)
		cout << "The Computer picked Rock." << endl;
	else if (getComputerChoice == 2)
		cout << "The Computer picked Paper." << endl;
	else if (getComputerChoice == 3)
		cout << "The Computer picked Scissors." << endl;
		cout << endl;
}
	
void winner(int UserChoice, int ComputerChoice)
	{
	if (UserChoice == 1)
	{
		if (ComputerChoice == 1)
			cout << "It's a tie, no one wins!" << endl;
		else if (ComputerChoice == 2)
			cout << "You lose." << endl;
		else if (ComputerChoice == 3)
			cout << "You Win!" << endl;
	}
	else if (UserChoice == 2)
	{
		if (ComputerChoice == 2)
			cout << "It's a tie, no one wins!" << endl;
		else if (ComputerChoice == 3)
			cout << "You lose." << endl;
		else if (ComputerChoice == 1)
			cout << "You Win!" << endl;
	}
	else if (UserChoice == 3)
	{
		if (ComputerChoice == 3)
			cout << "It's a tie, no one wins!" << endl;
		else if (ComputerChoice == 1)
			cout << "You lose." << endl;
		else if (ComputerChoice == 2)
			cout << "You Win!" << endl;
	}
	
	cout << "Thanks for playing! Please play again!" << endl;
	cout << endl;
}
Last edited on
zoran404 (263)
The algorithm used by rand function will give you random numbers, but always the same.
Use current time as seed to always get different random number:

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srand(time(0)); // <-- altering the algorithm
rand();


Also you should assign the value to getComputerChoice in your comp function (use a pointer), otherwise you will have get a random number, but it will be the same one as long as your program is running.

And a tip: use switch instead of if else ;)
Last edited on
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