Thread: Using boolalpha to print true and false but a little confused here

  1. #1
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    Using boolalpha to print true and false but a little confused here

    I'm using the iomanip header and boolalpha to print the words "true" and "false". I have a program that demonstrates a simple use of boolean variables. It goes like this:

    Code:
    #include <iomanip>
    #include <conio.h>
    using namespace std;
    
    int main()
    {
        bool b;
        
        b = false;
        
        cout << "b is " << b << endl;
        cout << "In other words, b is " << boolalpha << b << endl << endl;
        
        b = true;
        
        cout << "b is " << b << endl;
        cout << "In other words, b is " << boolalpha << b << endl << endl;
        
        if(b)
            cout << "Karen has a boatload of problems, but she's not all bad." << endl;
            
        b = false;
        
        if(b)
            cout << "Jerry is a nice guy...but actually that's a lie" << endl;
            
        cout << "13 > 11 is " << (13 > 11);
        
        getch();
        return 0;
    }
    When I run it the first two cout statements look fine:

    b is 0
    In other words, b is false

    No problem there but when I run the next two cout statements I see this:

    b is true
    In other words, b is true

    So I'm wondering why the compiler is not printing "b is 1" before I specifically instruct it to print "b is true" in the following statement?

    I'm guessing that when I use boolalpha for the first time in the cout statement, that is setting it for the rest of the program? Do I need to shut it off before I use it again?

  2. #2
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