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infinite loop problem

Jhub (56)
working on "ex 3" at bottom of code
I am trying to write a coin toss program that uses rand() to come up with the number 1 or 0.
Each one represents heads or tails.
The program asks the user "coin toss?"
The user inputs either yes or no
no stops the program
yes generates a coin toss with either heads or tails, then asks the user "coin toss".
Right now my while loop will not stop, and it goes into an infinite loop even when "no" is entered?
Why is this?
If no is entered it should not even execute the loop right?


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#include <iostream>
#include <cstdlib>
#include <ctime>
#include <iomanip>

using namespace std;

int main ()
{
    srand(time(0));
    char ch;
    int ex;
    cout<<"Which excerise? ";
    cin>>ex;
    cout<<endl;
    if (ex == 1)
    {
            double beg, end;
            int num;
        
            cout<<"Enter beginning and ending numbers, seperated by space: "<<endl;
            cin>>beg;
            cin>>end;
            cout<<endl;
    
            for (num=beg; num<=end; ++num)
            {
                    cout<<num<<","<<" ";
            }
            cout<<endl;
            cout<<endl;
    
            cout<<"Enter beginning and ending numbers, seperated by space: "<<endl;
            cin>>beg;
            cin>>end;
            cout<<endl;
    
            for (num=beg; num<=end; num++)
            {
                    cout<<num<<","<<" ";
                    num+=1;
            }
            cout<<endl;
            cout<<endl;
    
            cout<<"Enter the beginning and largest positive numbers, seperated by space: "<<endl;
            cin>>beg;
            cin>>end;
            cout<<endl;
    
            for (num=beg; num<=end; num)
            {
                    cout<<num<<","<<" ";
                    num*=-2;
            }
            cout<<endl;
            cout<<endl;
    }
    if (ex == 2)
    {
            int grade;
            double A, B, C, D, F;
            A=0;
            B=0;
            C=0;
            D=0;
            F=0;
    
            cout<<"Enter one or more grades, or -1 to stop:"<<endl;
        
            do 
            {
                    cin>>grade;    
        
                    if (grade>=90) A++;
			        if ((grade>=80) && (grade<=89)) B++;
			        if ((grade>=70) && (grade<=79)) C++;
			        if ((grade>=60) && (grade<=69)) D++;
			        if ((grade>=0) && (grade<=59)) F++;
            }
            while (grade!=-1);
        
            
            {
                    cout<<"The grades breakdown is:"<<endl;
                    cout<<"A's: "<<A<<endl;
                    cout<<"B's: "<<B<<endl;
                    cout<<"C's: "<<C<<endl;
                    cout<<"D's: "<<D<<endl;
                    cout<<"F's: "<<F<<endl;
            }
    }
    if (ex == 3)
    {
            double again, yes;
            int heads, tails;
        
            cout<<"Toss the coin? "<<endl;
            cin>>again;
            
            while (again==yes)
            {   
                    int random_number = rand()%2;
                
                    if (random_number==0)
                    {
                            cout<<"Heads"<<endl;
                    }
                    if (random_number==1)
                    {
                            cout<<"Tails"<<endl;
                    }
            }
            
    }

    
return 0;
}
Jhub (56)
do I need a break; after the if statements?
S G H (2638)
What are yes and again's type?
Jhub (56)
I managed to end the infinite loop but now if the user inputs yes for coin toss it only toss once and does not ask the user for another coin toss, it does the same thing for "no"

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if (ex == 3)
    {
            double again, yes, no;
            int heads, tails;
        
            cout<<"Toss the coin? "<<endl;
            cin>>again;
            
            do
            {
                    
                    int random_number = rand()%2;
                
                    if (random_number==0)
                    {
                            cout<<"Heads"<<endl;
                            break;
                    }
                    if (random_number==1)
                    {
                            cout<<"Tails"<<endl;
                            break;
                    }
            }
            while (again==yes);
            
    }

    
return 0;
}
S G H (2638)
You only got your problem worse.
Jhub (56)
your right, I went back to original code.
yes and again are doubles, no?
Jhub (56)
back to infinite loop :(
S G H (2638)
Yes, they are doubles. Nothing wrong with this, "right?"
Jhub (56)
but now I just get the infinite loop no matter if "no" or "yes" is selected.
igorbez (30)
now is good time to improve your debugging skills! :)
what the 'again' variable gets from the user?
the user input needs to be part of the loop, to be able to exit the loop..
Last edited on
Jhub (56)
Thanks igor I did put the cout and cin statements in the loop and the loop still does not stop it only displays the cout and continues in its infinite madness
igorbez (30)
so debug it step by step, put a watch on the 'again' variable to check what it conteins for the loop duration..
S G H (2638)
Take it one step at a time.
What is a double? How can a double store a yes/no?
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