Why aren't my if else codes working? - c++

I am making a simple random number guesser game (example below), and it works perfectly until your guess is higher than the number. when it happens, it prints: "My number is lower than thatMy number is higher than that" When it is just supposed to print "My number is lower than that". Also, when you guess the right answer, it prints "My number is higher than that"
My code is:
#include <iostream>
#include <unistd.h>
#include <cstdlib>
int main() {
int highnum;
int guess;
srand(time(0));
std::cout << "Pick a number greater than 2";
std::cin >> highnum;
int randynumeber = (rand () % highnum) + 1;
std::cout << "I have picked a random number between 1 and " << highnum << " which you need to try and guess";
int guesses = 0;
int stop = 0;
while (guess != randynumeber)
{
if (stop == 0)
{
sleep(0.1);
stop = 1;
std::cout << std::endl << "Guess a number";
std::cin >> guess;
if(guess>randynumeber)
std::cout << "My number is lower than that";
else if(guess<randynumeber)
std::cout << "My number is higher than that";
stop = 0;
}
}
std::cout << std::endl << "guesses = " << guesses;
std::cout << "You win!";
}

You are not testing the condition on the else statement. You need to test it otherwise it simply executes ( guess < randynumeber); - which gives a logic answer and then executes the next piece of code which is the next cout statement.

Related

For loop - Magic number program

What changes should I make so that the user of this code can guess at the amount of magic numbers they choose, with three different chances to guess at each magic number? I am also confused on what to change so that the magic number can change once the user guesses the magic number correctly.
#include <iostream>
#include <cstdlib>
#include <ctime>
#include <cstdio>
using namespace std;
int main()
{
int magic; // This is a random number between 1 and 20
int guess; // This is the guess number being attempted (up to 3 guesses)
int magicguesses; // This is the amount of magic numbers being guessed attempted
int i;
int number; // This is the number the user guessed
bool numberismagic = false; // This is the flag variable
unsigned int seed;
seed = time(NULL);
srand(seed);
magic = rand() % 20 + 1;
cout << "How many magic numbers would you like to guess at today?\n";
cin >> magicguesses;
for (i = 1; i < magicguesses + 1; i++)
{
cout << "This is trial number:" << i << endl;
for (guess = 1; (guess < 4) && (!numberismagic); guess++)
{
cout << "This is guess number:" << guess << endl;
cout << "Guess a number between 1 and 20:" << endl;
cin >> number;
while ((number < 1) || (number > 20))
{
cout << "Your guess is invalid; guess a number between 1 and 20 \n";
cin >> number;
cout << endl;
}
if (number == magic)
{
cout << "You have guessed the magic number correctly! \n";
numberismagic = true;
}
else
{
cout << "Sorry - you guessed incorrectly! \n";
if (number > magic)
cout << "Your guess is too high \n" << endl;
else
cout << "Your guess is too low \n" << endl;
}
}
if (number != magic)
cout << "The magic number is:" << magic << endl;
}
return 0;
}
I'm not sure what your first question is, but for this question "I am also confused on what to change so that the magic number can change once the user guesses the magic number correctly", you should edit the variable magic inside the first for loop so the magic number changes after the user guesses correctly or they run out of tries.
for (i=1;i<magicguesses+1;i++)
{
//magic equals new random number
//the rest of your code
}

C++ simple game using a Loop program

This program will play a game with the user, called Odds and Evens. The computer will play Evens, and the human user will play Odds. For a round of the game, each player picks an integer in the range [1,10]. The players pick their numbers independently: neither player knows the other player's number before choosing its own number. If the sum of the numbers is even, then Evens (the computer) wins that round; if the sum of the numbers is odd, then Odds (the human) wins that round. The game continues for as many rounds as the user want to play; the user ends the game by typing a non-# or a number outside [1,10] for the input. At the end of the game, the program summarizes the score.
I am having trouble properly looping this question. Randomizing the number pc chooses is not working as every round in the game the pc chooses the same number. Also i do not know how I would have the program summarize the score. Help would be much appreciated as I have another problem for homework that is similar to this!
Here is my code:
#include <iostream>
#include <cmath>
#include <cstdlib>
#include <string>
#include <iomanip>
#include <ctime>
using namespace std;
bool die(const string & msg);
int main(){
srand(static_cast<unsigned>(time(0)));
unsigned num1 = 0, num = 0, sum = 0;
bool userTurn = true;
cout << "Welcome to the Odds and Evens game!";
num = rand() % 10 + 1;
while (num){
if (userTurn){
cout << " Your # in [1,10] is ";
cin >> num1;
}
else {
cout << "My number is " << num;
sum = num1 + num;
if (sum % 2 == 0){
cout << " I win!";
}
else {
cout << " You win!";
}
}
userTurn = !userTurn;
}
}
bool die(const string & msg){
cout << "Fatal error: " << msg << endl;
exit(EXIT_FAILURE);
}
Randomizing the number pc chooses is not working as every round in the game the pc chooses the same number.
You don't have code to re-set the value of num when it's the computer's turn.
After the line
userTurn = !userTurn;
add
if ( !userTurn )
{
num = rand() % 10 + 1;
}
Also i do not know how I would have the program summarize the score.
Keep two counters that indicate how many times the human won and how many times the computer won.
int computerWinCount = 0;
int humanWinCount = 0;
and then, update the loop to use:
if (sum % 2 == 0){
cout << " I win!";
++computerWinCount;
}
else {
cout << " You win!";
++humanWinCount;
}
The conditional of the while loop is such that your program will never terminate. Update it to something like below.
while (true) {
if (userTurn){
cout << " Your # in [1,10] is ";
cin >> num1;
// If the user entered a number that is not
// within range or the user did not input a number,
// then break out of the loop.
if ( !cin || num1 < 1 || num1 > 10 )
{
break;
}
}
else {
cout << "My number is " << num;
sum = num1 + num;
if (sum % 2 == 0){
cout << " I win!" << endl;
++computerWinCount;
}
else {
cout << " You win!" << endl;
++humanWinCount;
}
}
userTurn = !userTurn;
if ( !userTurn )
{
num = rand() % 10 + 1;
}
}
To report the summary, add the following lines before the end of the main.
cout << "Number of times I won: " << computerWinCount << endl;
cout << "Number of times you won: " << humanWinCount << endl;
Here:
num = rand() % 10 + 1;
while (num){
... // never change num
}
Do you see the problem? The computer player chooses num randomly, but only once. Just put another num = rand() % 10 + 1; inside the main loop.
(Also, you don't seem to have a way for the user to terminate the game.)
So you want a simple loop that will do the following things.
get the user input.
get the computer input
check to see who win's the current round
update scores.
this happens until the user chooses an option not from 1 to 10
after this you want to display the score.
Here is a complete example.
#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
int main(){
int mynum, compNum, myScore(0), compScore(0);
srand(time(NULL));
cout << "Welcome to the Odds and Evens game!" << endl;
cout << "Your # in [1,10] is ";
while ((cin >> mynum) && mynum > 0 && mynum <= 10){
compNum = rand()%10 + 1;
if ((mynum + compNum)%2){
cout << "You win" << endl;
++myScore;
} else {
cout << "Computer Wins" << endl;
++compScore;
}
cout << "Your # in [1,10] is ";
}
cout << "You won " << myScore << " games" << endl;
cout << "The computer won " << compScore << " games" << endl;
return 0;
}
Your problem with the computer's number not changing is due to the fact you do not update its value within the loop.
If you want to keep track of the score, you can simply keep two integers that keep track of how many times the user has won and how many times the computer has won. Then at the end (after the while loop) cout each of their scores.
Overall your code is pretty close.
You just need to make sure you update the computer's guess inside the while loop and when you decide who's won the round increment that person's score.
The whole loop condition in your original code will always evaluate to true. As num will always be to a number 1 to 10. You'll want to use the user's input in the while loop condition.
The while condition in my code will do the following:
get the user's input. cin >> mynum will evaluate to false if cin fails to read a number. If it did read a number the condition will check to see if the number is between 1 and 10 inclusive.

Simple Number Guessing Game. C++

I've been trying to make a simple game where the computer generates a random number and you try to guess it. It also stores the amount of guesses you make "tries".
However, when I run the program, it simply prints: "Let's play a game. I'll think of a number 1-100. Try to guess it."
Here's my code:
#include <iostream>
int main()
{
using namespace std;
int the_number;
int guess;
int tries;
the_number = rand() % 101 + 1;
cout << "Let's play a game!";
cout << "I will think of a number 1-100. Try to guess it.";
cout << endl;
cin >> guess;
for (tries = 0; tries++;)
{
if (guess == the_number)
{
cout << "You guessed it!";
cout << "And it only took you: " << tries;
}
else if (guess < the_number)
{
cout << "Higher";
tries++;
}
else if (guess > the_number)
{
cout << "Lower";
tries++;
}
else
cout << "That's not even in range!";
return 0;
}
}
I don't understand why this doesn't work, could someone explain why not?
The reason your program does not print anything after "Let's play a game. I'll think of a number 1-100. Try to guess it." is the way you have written your for loop.
for ( tries = 0; tries++; )
breaks out of the loop without doing anything because tries++ evaluates to 0.
Also, for your program to work correctly, you need to add more code to read guesses. Something like the code below, should work.
for (tries = 0; ; tries++)
{
if (guess == the_number)
{
cout << "You guessed it!";
cout << "And it only took you " << tries << " tries.\n";
break;
}
else if (guess < the_number)
{
cout << "Higher";
cin >> guess;
}
else if (guess > the_number)
{
cout << "Lower";
cin >> guess;
}
}
You can define a couple of variables that will make your code more understandable, something like this :
#include <iostream>
using namespace std;
int main()
{char EndGame = 'N';
int MyNumber = 150 , playerguess;
cout << "I have a number between 1 and 100.\nCan you guess my number ??\nPlease type your first guess.\n?" << endl;
do{
cin >> playerguess;
if (playerguess > MyNumber) {
cout << " Too High. Try again." << endl;
}
else if (playerguess == MyNumber) {
cout << "Excellent ! You Got It ! \n If you want to exit press Y" << endl;
cin >> EndGame;
break;
}
else {
cout << " Too Low. Try again." << endl;
}
} while (1);
return 0;
}
This will make the number equal to 150. Each time the user inputs a value, the console will determine whether it is higher, lower or equal to the number.
If you want instead to make it a random number each time, you can simply use the <random> library and use the module operator with a number like 100 or 101. Then, you can add 1; this will generate only positive integers.
You should use while loop here, not for:
while (the_number != guess)
{
//
//
}
And try using the new <random> header instead of rand() function:
#include <random>
std::random_device rd;
std::default_random_engine engine(rd());
std::uniform_int_distribution<int> uniform_dist(1, 100);
the_number = uniform_dist(engine);
Your for loop is wrong (it needs 3 things: initialization, check condition and the todo step after each loop.
For example:
for (tries = 0; tries < 5; tries++)
Also you loop the guessing part, but you forget to ask the user for a new number. I would suggest to move the cin << guess into the for loop.

I've know idea where to look, maybe it's an infinite loop? (C++, using VS2012) [closed]

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Closed 10 years ago.
Well, I'll introduce myself first. I'm Ben, a 17-years old 'game-programmer' from the Netherlands who just has begun to program in C++ (started about a month ago, but programming for a year right now) (and I'm using Microsoft Visual Studio 2012 as compiler). Now, I am 'learning it myself' but I still do use a book and that book is called 'Beginning C++ Through Game Programming, Third Edition' by Michael Dawson.
I just did finish with chapter two and the last excersize was: "Write a new version of the Guess My Number program in which the player and the computer switch roles. That is, the player picks a number and the computer must guess what it is."
Here follows the code of the 'Guess My Number' Program:
// Guess My Number
// The classic number guessing game
#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
int main()
{
srand(static_cast<unsigned int>(time(0))); //seed random number generator
int secretNumber = rand() % 100 + 1; // random number between 1 and 100
int tries = 0;
int guess;
cout << "\tWelcome to Guess My Number\n\n";
do
{
cout << "Enter a guess: ";
cin >> guess;
++tries;
if (guess > secretNumber)
{
cout << "Too high!\n\n";
}
else if (guess < secretNumber)
{
cout << "Too low!\n\n";
}
else
{
cout << "\nThat's it! You got it in " << tries << " guesses!\n";
}
} while (guess != secretNumber);
return 0;
}
Now, I was busy with thinking, programming testing and it just wouldn't work.
It seems I got stuck with such a infinite loop. But I can't find the problem.
Here's the code, and other ways to fix this are welcome, just keep in mind that I don't know a lot of the language. ;)
// Guess My Number 2
// The classic number guessing game with a twist
#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
int main()
{
srand(static_cast<unsigned int>(time(0)));
int secretNumberComputer = rand() % 100 + 1;
int secretNumberPlayer;
int triesPlayer = 0;
int triesComputer = 0;
int guessPlayer;
int guessComputer;
int tooHighPlayer;
int tooLowPlayer;
int correctPlayer;
int tooHighComputer;
int tooLowComputer;
int correctComputer;
int selectNumberIncorrect;
int lowerGuessComputer = 101;
int higherGuessComputer = 0;
cout << "Welcome to Guess My Number\n\n";
do
{
cout << "Enter a guess: ";
cin >> guessPlayer;
++triesPlayer;
tooHighPlayer = (guessPlayer > secretNumberComputer);
tooLowPlayer = (guessPlayer < secretNumberComputer);
correctPlayer = (guessPlayer == secretNumberComputer);
if (tooHighPlayer)
{
cout << "Too high!\n\n";
}
else if (tooLowPlayer)
{
cout << "Too low!\n\n";
}
else if (correctPlayer)
{
cout << "\nThat's it! You got it in " << triesPlayer << " guesses!\n\n";
break;
}
else
{
cout << "Error, check code!\n\n";
break;
}
} while (!correctPlayer);
cout << "Now it's time for you to pick a number and then the computer will guess.\nEnter a number between 1 and 100: ";
do
{
cin >> secretNumberPlayer;
selectNumberIncorrect = (secretNumberPlayer > 100 || secretNumberPlayer < 1);
if (selectNumberIncorrect)
{
cout << "\nHey, that isn't a number between 1 and 100! Please pick a number that is: ";
}
else
{
break;
}
} while (selectNumberIncorrect);
guessComputer = (rand() < lowerGuessComputer && rand() > higherGuessComputer);
cout << "\n\nNow the computer is going to try to guess your number:" << endl;
cout << "Computer, take a guess: " << guessComputer << endl;
++triesComputer;
tooHighComputer = (guessComputer > secretNumberPlayer);
tooLowComputer = (guessComputer < secretNumberPlayer);
correctComputer = (guessComputer == secretNumberPlayer);
lowerGuessComputer = (rand() % 100 + 1 && rand() < guessComputer);
higherGuessComputer = (rand() % 100 + 1 && rand() > guessComputer);
if (tooHighComputer)
{
cout << "Too High!\n\n";
guessComputer = lowerGuessComputer;
}
else if (tooLowComputer)
{
cout << "Too Low!\n\n";
guessComputer = higherGuessComputer;
}
else if (correctComputer)
{
cout << "\nThat's it! You got it in " << triesComputer << " guesses!\n\n";
}
else
{
cout << "Error, check code!\n\n";
}
do
{
cout << "Computer, take a guess: " << guessComputer << endl;
++triesComputer;
if (tooHighComputer)
{
cout << "Too High!\n\n";
guessComputer = lowerGuessComputer;
}
else if (tooLowComputer)
{
cout << "Too Low!\n\n";
guessComputer = higherGuessComputer;
}
else if (correctComputer)
{
cout << "\nThat's it! You got it in " << triesComputer << " guesses!\n\n";
break;
}
else
{
cout << "Error, check code!\n\n";
break;
}
} while (!correctComputer);
if (triesComputer < triesPlayer)
{
cout << "You lost against the computer!\n\n";
}
else if (triesComputer > triesPlayer)
{
cout << "You won!\n\n";
}
else
{
cout << "It's a tie!\n\n";
}
cout << "Thank you for playing! Goodbye!" << endl;
return 0;
}
In this block you aren't checking the computer's guess for correctness (assigning correctComputer), so the loop continues forever, unless it guessed correctly the first time.
do
{
cout << "Computer, take a guess: " << guessComputer << endl;
++triesComputer;
if (tooHighComputer)
{
cout << "Too High!\n\n";
guessComputer = lowerGuessComputer;
}
else if (tooLowComputer)
{
cout << "Too Low!\n\n";
guessComputer = higherGuessComputer;
}
else if (correctComputer)
{
cout << "\nThat's it! You got it in " << triesComputer << " guesses!\n\n";
break;
}
else
{
cout << "Error, check code!\n\n";
break;
}
} while (!correctComputer);
Your second do loop never recalculates the computer's guess.
i.e. you have the computer guess one number before the do loop, then in the loop you keep checking if that one guess is too high or too low, never recalculating its value. It'll obviously never end.
You need to do the computer's guess calculation inside the second loop.
EDIT
Also, this logic is incorrect:
lowerGuessComputer = (rand() % 100 + 1 && rand() < guessComputer);
higherGuessComputer = (rand() % 100 + 1 && rand() > guessComputer);
The guess will always be 0 or 1 because the result of the right-hand-side operation is a boolean. In fact, I don't know what you're trying to do there. You're performing && between an integer and a boolean. I also don't understand why you are calculating two different guesses - you should calculate one number within the range of the higher/lower parameters you were given.
In addition to what Kevin Tran wrote, please check the valid input type for cin.
Imagine someone typing characters instead of integers.
so
cin >> guessPlayer;
can be written as
if (cin >> guessPlayer) {
// Do you logic here
}
else {
cout<<"Enter numbers only. :)";endl;
continue;
}
Hope this helps.
Instead of analyzing the code you posted which has numerous flaws, let's just think about what your program has to do: The user will pick a random number, and the computer will try to guess that number.
So, your program flow should go like this:
The computer picks a random number. It prints it out and asks the user to choose if the number is too high, too low or correct. (i.e. by asking the user to type '1' if too high, '2' if too low or '3' if it's right).
If the user types '3' then obviously you're done.
If it's too high, the computer picks a new random number (smaller than it's last guess) and tries the above logic again.
If it's too low, the computer picks a new random number (greater than it's last guess) and tries the above logic again.
Now let's try and implement some code that implements the above:
using namespace std;
int main()
{
int range_low = 0; // The number the user picked is greater than this
int range_high = 100; // The number the user picked is smaller than this
srand(static_cast<unsigned int>(time(0)));
do
{
// We want to generate a random number between range_low and range_high. We do this
// by generating a random number between zero and the difference of "low" and "high"
// adding it to low and adding one more.
int guess = range_low + ((rand() % (range_high - range_low)) + 1);
cout << "I'm guessing your number is " << guess << "... how did I do?" << endl
<< " [1: too high, 2: too low, 3: you got it!] ";
// Now let's see how we did...
int choice;
cin >> choice;
if(choice == 3)
{
cout << "Be amazed at my psychic powers! For I am a computer!" << endl;
break;
}
if(choice == 2)
{
cout << "Hmm, ok. I was sure I had it. Let's try again!" << endl;
range_low = guess;
}
if(choice == 1)
{
cout << "Really? Ok, ok, one more try!" << endl;
range_high = guess;
}
} while(true);
return 0;
}
Here are two exercises for you to improve the above:
First, try to compare the logic of this code against the logic of your code and see where your code differs - try to understand why it was wrong. It will help to try to execute the program using pen and paper, just like you were a computer that understood C++.
Second, try to add code to ensure that the computer never guesses the same number twice.

while loop acting up... not doing what it should for some reason

I have this code for a simple Dice throwing program with betting units and everything... you bet, if you get it right you get the amount u bet times the amount of dice you chose... if you're wrong but by a little (in the range of the number you picked +- the number of dice u picked) you don't lose anything, and if you're really off you lose...
I have a while loop that basically keeps 2 things in mind: as long as the user either has BUs or if they didn't type "no" or "No" for the try again... but for some reason it just doesn't work... lol. any ideas why? the betting system works, it recognizes that betting.currentBU == 0, but the while loop just won't react lol.
#include <iostream>
#include <string>
#include <cstdlib>
#include <time.h>
#include <limits>
using namespace std;
struct Dices{ // structure containing all the dice related integers
int dice;
int total;
int choice;
} Dices = {0,0,0};
struct betting{ // structure containing all the betting integers
int currentBU;
int bettedBU;
} betting = {100, 0};
int DiceThrow(int dicechoice, int totalnum){ // a method for the dice being rolled
for(int i=1; i <= dicechoice;i++){
totalnum = totalnum + (rand() % 6 + 1); //total number, repeated by the loop for every dice
}
return totalnum;
}
int winningbet(int dicea, int cBU, int bBU){ // in case the user guesses it right
std::cout << "Congratulations, you got it right! \n";
cBU = cBU + (dicea * bBU); // give him money...
return(cBU);
}
int losingbet(int dicen, int totaln, int choicen, int cBU2, int bBU2){ //in case the user guesses wrong
if(choicen > (totaln+dicen) || choicen < (totaln+dicen)) // checks how wrong he is, if he's too off, he loses BUs
cBU2 = cBU2-bBU2;
else
std::cout << "you we're so close, you don't lose any BUs! \n"; //if he was really close, just let him know he was close
return(cBU2);
}
int main(){
string decision; // decision if they want to keep playing or not
srand ( (unsigned int)time(NULL) );
while(decision != "no" || decision != "No" || betting.currentBU != 0) // makes sure of the decision AND that he still has BUs
{
Dices.total = 0;
std::cout << "how many dice would you like to use? ";
std::cin >> Dices.dice;
std::cout << "how many How many BUs are you betting?(" << betting.currentBU << " BUs left) ";
std::cin >> betting.bettedBU;
if(betting.bettedBU > betting.currentBU){ // if he doesn't have enough BUs
std::cout << "Sorry, you don't have that many BUs...";
std::cout << "Want to try again with a different amount?(Yes/No) ";
std::cin >> decision;
}
else{
std::cout << "guess what number was thrown: ";
std::cin >> Dices.choice;
Dices.total = DiceThrow(Dices.dice, Dices.total);
if(Dices.choice == Dices.total){
betting.currentBU = winningbet(Dices.dice, betting.currentBU, betting.bettedBU);
std::cout << "Want to try again?(Yes/No) ";
std::cin >> decision;
} else{
std::cout << "Sorry, the number was " << Dices.total << "... better luck next time \n" ;
betting.currentBU = losingbet(Dices.dice, Dices.total, Dices.choice, betting.currentBU, betting.bettedBU);
if(betting.currentBU > 0){
std::cout << "Want to try again?(Yes/No) ";
std::cin >> decision;
}
}
}
}
if(betting.currentBU == 0){
std:cout << "sorry, you ran out of BUs...";
std::cin.ignore( std::numeric_limits<std::streamsize>::max(), '\n' );
}
else{
std::cout << "your final BU count is: " << betting.currentBU << "\n";
std::cout << "Thanks for playing, see you next time! (Press ENTER to terminate...)";
std::cin.ignore( std::numeric_limits<std::streamsize>::max(), '\n' );
}
return 0;
}
isn't it supposed to be:
while(decision != "no" && decision != "No" && betting.currentBU != 0)
We need to check if decision not equal to "no" AND not equal to "No" AND the currentBU not equal to 0
Your test is while (A || B || C), which will loop as long as ANY of those three things are true. Since decision can't be equal to both "no" and "No" at the same time, at least one of those two not-equals tests will always be true, so the loop will loop forever...