cin.get(); doesn't work even with cin.ignore();

I have just started to learn C++ and find it very fun. I know VB very well and know a bit of Pascal. I was writing my first program and this is all the code.

Code:

---

#include <iostream.h>
#include <stdlib.h>

using namespace std;

int main()
{
 cout<<"Hello\n";
cout<<"Please enter your name\n";

int name;

cin>> name;
cin.ignore();
cout<<"Now enter your age\n";

int age;

cin>> age;
cin.ignore();
cout<<"So you are called"<< name <<"and you are"<< age <<"years old\n";
cin.get();
}

---

The program is VERY simple and it is meant to ask for your name and age and then say it back to you. When it starts is says this:

Hello
Please enter your name

I enter my name and press enter but instead of asking me how old I am it ends the program. I searched the forum and found a thread that said to add cin.ignore(); so that the enter was ignored. I added this but the same thig happens. Debbuging finds nothing and I don't know how to fix it.
Any help would be goo
Thanks
Calum N :confused:

Several things. First you are trying to read a name (which is a string) into an int variable, which holds a number. That won't work. You have to #include <string> and make name a string variable. Second, you are using <iostream.h> which is outdated and non-standard. Switch to <iostream>. Finally, make sure that when you enter your name, you only enter one word. You can code your program so that it can take in multiple words, but that is more advanced so don't try to do that just yet.

Change

Code:

---

int name;

---

to

Code:

---

char name[256];

---

Thanks Dave and cunnus
I thought about iostream.h but Dev C++ had iostream.h as the default so I left it.
Thanks

Or do what davide said and:

Code:

---

#include <string>

string name

---

Do you know how to change what Dev-C++ shows you when you make a new source?

>> char name[256];
I would not do that. There's no reason to use a C style string here.

Use string instead.

I have changed the char thing into string.
I wondered what char did.
I don't know how to change what Dev C++ shows.
I have added if things so that it says whether you are a child or an adult
This is my updated code:

Code:

---

#include <iostream>
#include <stdlib.h>
#include <string>

using namespace std;

int main()
{
 cout<<"Hello\n";
cout<<"Please enter your first name and press enter\n";

string name;

cin>> name;
cin.ignore();
cout<<"Now enter your age\n";

int age;

cin>> age;
cin.ignore();
cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";
if ( age < 18) {
cout<<"You are a child!\n";
}
else if ( age > 19) {
cout<<"You are old\n";
}

cin.get();
return 0;
}

---

Quote:

---

Originally Posted by calumn

I have changed the char thing into string.
I wondered what char did.

---

string is a C++ implementation of a char array with checks and boundaries and dynamic allocation and more all rolled into a nice transparent package.

Code:

---

if ( age < 18) {
cout<<"You are a child!\n";
}
else if ( age > 19) {
cout<<"You are old\n";
}

---

Well that's great, but what if, when asked, the user enters 18? Your program explodes. Fix that.

I have been working on it a bit and have been using more advanced ifs.

Code:

---

#include <iostream>
#include <stdlib.h>
#include <string>

using namespace std;

int main()
{
 cout<<"Hello\n";
cout<<"Please enter your first name and press enter\n";

string name;

cin>> name;
cin.ignore();
cout<<"Now enter your age\n";

int age;

cin>> age;
cin.ignore();
cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";
if ( age <= 12 and age > 0) {
cout<<"You are a child!\n";
}
else if ( age >= 13 and age <= 19) {
cout<<"You are a teenager\n";
}
else ( age > 19 and age <= 55) {
cout<<"You are an adult\n";
}
cin.get();
return 0;
}

---

I added another else but it doesn't seem to work
I will add another one saying over 55 after i get this to work but it doesn't seem to.

These are the errors:
c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp: In function `int main()':

c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp:23: parse error before `age'

c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp:25: confused by earlier errors, bailing out

Thanks for all your help

'and' isn't a C++ keyword... you need '&&'

I used to have the && but someone on msn told me to change it to and and it still worked.
I have changed the and back into && but it still gives me the exact same errors

Yay I fixed it:

Code:

---

{
 cout<<"Hello\n";
cout<<"Please enter your first name and press enter\n";

string name;

cin>> name;
cin.ignore();
cout<<"Now enter your age\n";

int age;

cin>> age;
cin.ignore();
cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";
if ( age <= 12 && age > 0) {
cout<<"You are a child!\n";
}
else if ( age >= 13 && age <= 19) {
cout<<"You are a teenager\n";
}
else if ( age > 19 && age <= 55) {
cout<<"You are an adult\n";
}
cin.get();
return 0;
}

---

I didn't have an if after the last else

>> 'and' isn't a C++ keyword... you need '&&'
Yes, it is. However, you should probably just use && since that is the more commonly used version.

It worked fine both ways
I have added it so it will always tell you your age like a child or teenager

Code:

---

#include <iostream>
#include <stdlib.h>
#include <string>

using namespace std;

int main()
{
 cout<<"Hello\n";
cout<<"Please enter your first name and press enter\n";

string name;

cin>> name;
cin.ignore();
cout<<"Now enter your age\n";

int age;

cin>> age;
cin.ignore();
cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";
if ( age <= 12 && age > 0) {
cout<<"You are a child!\n";
}
else if ( age >= 13 && age <= 19) {
cout<<"You are a teenager\n";
}
else if ( age > 19 && age <= 55) {
cout<<"You are an adult\n";
}
else if ( age > 55) {
cout<<"You are ancient\n";
}
else if ( age < 0) {
cout<<"You haven't been born yet\n";
}
cin.get();
return 0;
}

---

Looks good.

A couple extra things to consider if you want. First, I prefer to start with a completely empty file. I don't like that Dev-C++ starts you off with non-standard code, but I also think its better to just understand what you need and put it in when you need it. For example, you don't need <stdlib.h> in that program. You do need <iostream> for cout and cin, and you do need <string> for the string class. If you understand that, then for the next program you write you can decide which you need and only use those.

A second thing is to work on your indenting (unless the forum software messed it up). Each time you add a new scope (basically in between your braces for the main function and the ifs and else ifs) you should indent the code four more spaces than the previous line. When the scope ends at the closing brace, go back to the previous indentation level. For example:

Code:

---

    if ( age <= 12 && age > 0) {
        cout<<"You are a child!\n";
    }

---

Quote:

---

Originally Posted by calumn

I used to have the && but someone on msn told me to change it to and and it still worked.
I have changed the and back into && but it still gives me the exact same errors

---

yeah, my mistake, I forgot that worked in C++ too... and don't listen to what people on msn tell you and don't read the msdn... evil lurks there.

To change what Dev-C++ shows:

1. Go to options
2. Click on Environment Options
3. Select the Misc. tab
4. Change the code and press ok

See they keep saying use && because its good programming practice and would sometimes bail half way out and you might get something wrong outputed.

"and" is only there because some people in the remote mountains of Tahiti may not have "&" symbols on their typewriters. IMO you should refrain from using it whenever possible, as that is rather non-standard coding practice.

Ok I wont use "and again.
Do I need

Code:

---

using namespace std;

---

at the start of every thing I make because It says to put it there in the tutorials but Dev C++ didn't have it there.
I have added it anyway
The program works fine with and without using namespace std; at the top. I kept it there anyway.
This is my updated code and it tells you if you are an adult or child etc. even if you enter something like -22.

Code:

---

#include <iostream>
#include <string>

using namespace std;

int main()
{
 cout<<"Hello\n";
cout<<"Please enter your first name and press enter\n";

string name;

cin>> name;
cin.ignore();
cout<<"Now enter your age\n";

int age;

cin>> age;
cin.ignore();
cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";
if ( age <= 12 && age > 2) {
    cout<<"You are a child\n";
}
else if ( age >= 0 && age <= 2) {
    cout<<"You are a baby\n";
}
else if ( age >= 13 && age <= 19) {
    cout<<"You are a teenager\n";
}
else if ( age > 19 && age <= 55) {
    cout<<"You are an adult\n";
}
else if ( age >= 65 && age < 100) {
    cout<<"You are and OAP\n";
}
else if ( age < 0) {
    cout<<"You haven't been born yet\n";
}
else if (age >= 100) {
    cout<<"You are antique\n";
}
cin.get();
return 0;
}

---

I also indented it before cout.
I am going to try and make it so that it asks you if the details are right and if you say yes if syas something like OK but if you say no it goes back to asking you your name.

Is it possible to use words inside and if statements
Say I made a string called right and then it asked the user is the information was right or wrong and then there was an if statement that said if the variable was == to yes then it would say ok but if the variable was == no it would say Oh well then. Sfter I got that to work I would add loops so that it would go back to the start if you said no.

Code:

---

cout<<"Is this right?\n";
string right;
cin>> right;
cin.ignore();

if ( right == yes) {
    cout<<"OK\n";
}
else if ( right == no) {
    cout<<"Thats good then\n";
}
cin.get();

---

I don't think it will work and I keep on getting errors while compiling:
c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp: In function `int main()':
c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp:48: `yes' undeclared (first use this function)
c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp:48: (Each undeclared identifier is reported only once
c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp:48: for each function it appears in.)
c:\docume~1\neilson\mydocu~1\progra~2\c__~1\abouty ~1.cpp:51: `no' undeclared (first use this function)
I think that it think that no and yes are a function.
Have I just done it wrong and is there a better way of doing it.
Thanks for all your help

You can do this, but you must first understand that there are rules
that the compiler uses to differentiate between variables and
literal text. The compiler errors are telling you that the compiler
thinks that yes and no are variables or a functions.

To make it do the comparison, put those words in quotes, "yes"
for example. Then your program will work because the compiler
knows it is text, refered to as a string literal.

Just an early warning though, this works fine for C++ strings,
but you will (sooner or later) come across C style strings - less
fancy and powerful. To do comparisons on those you need the
function strcmp (). No need to worry about it yet though.

Thanks
I have changed it to that and it works fine.
I have made it also ask you if it is right and it can tell if you are not telling the truth about your age.
This is the updated code
What do you think I should try to add next

Code:

---

#include <iostream>
#include <stdlib.h>
#include <string>
#include <stdio.h>

using namespace std;

int main()
{
cout<<"Hello\n";
cout<<"Please enter your first name and press enter\n";

string name;

cin>> name;
//Clear screen:

system("cls");
ageenter: /*Makes ageenter*/
cout<<"Now enter your age\n";

int age;

cin>> age;
system("cls"); /*Clears the screen*/
if (age < 1 ) {
    cout << name << ", you are not " << age << "\n";
goto ageenter; /*goes to ageenter*/
}
else if (age > 124 ) {
    cout << name << ", you are not " << age << "\n";
goto ageenter;
}
else
{
cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";

if ( age < 12 && age > 0 ) {
    cout<<"You are a child!\n";
}
else if ( age >= 13 && age <= 19) {
    cout<<"You are a teenager\n";
}
else if ( age > 19 && age <= 55) {
    cout<<"You are an adult\n";
}
else
{
    cout<<"You are elderly";
}
}

cout<<"Is this right?\n";
string right;
cin>> right;
if (right == "yes") {
    cout<<"OK\n";
    system("pause");
}
else if (right == "no") {
goto ageenter;
}

return 0;
}

---

I am trying to make it open in full screen.
I don't know how to do this but I asked one of my friends said you have to make it so that the program thinks that the user is pressing alt-enter by doing this:
Add the windows.h library and then add:

Code:

---

keybd_event(VK_MENU, MapVirtualKey(VK_MENU, 0), 0, 0);
    keybd_event(VK_RETURN, MapVirtualKey(VK_RETURN, 0), 0, 0);
    keybd_event(VK_RETURN, MapVirtualKey(VK_RETURN, 0), KEYEVENTF_KEYUP, 0);
    keybd_event(VK_MENU, MapVirtualKey(VK_MENU, 0), KEYEVENTF_KEYUP, 0);

---

Is it hard to make them so that they don't run in DOS/command prompt and run in a windows sort of thing if you know what I mean or is that way too hard.

Program works well, just a few tips though

1) The use of goto is "frowned upon" (thats the wording i see a
lot), basically due to the visual and logical effect that it has on
your code - programmers don't like to go looking for labels, and
repeated use leads to code that is difficult to follow and can cause
debugging issues (not from personal experience, I've never used
goto). Nevertheless, it seems to be very natural to beginners,
so that i suggest that the next couple of programs you write,
use goto and get a feel for controlling the flow of your program.
Then learn about loops - the more clearer and definite way to
achieve program flow control. Here's a link about them.

2) You don't need stdio.h for this program - thats a C header
anyway. Also, as for stdlib.h (also C), the C++ equivalent is
cstdlib (no .h). Either will work in this program, but just so you
know.

3) As for opening a console in full screen, yes Virtual Keyboard
(VK) is one way of doing it for you, but there is probably an
actual function in the windows header that allows you to do
this. I don't know any off the top of my head because I haven't
done any "windows programming," but perhaps someone else
can suggest a method. Nevertheless, I'd like to make the point
that since you are a beginner, messing with VK and windows
programming features is ill advised, because you are learning
code that is very system specific. You can do loads of things with
VK but that doesn't mean there isn't a simpler and better way to
do it with standard code. My advice is to hold back on
implementing such a feature.

4) Making it look like a windows dialog box is much much harder,
and with what i said in 3 above, you really should wait a good
while before you mingle with windows API programming.

5) Code indentation has been mentioned earlier on, but I thought
I'd reiterate here.

The next steps your program could make would be to allow the
user to enter yes or no in any case (i.e. YeS). Take a look at
a function called tolower or toupper, or compare to every
permutation of the letters (inefficient but it can be done). I won't
give you a specific way of doing this, so you can do some
investigations and find out for yourself. Nonetheless, if you
decide to try it and run into problems, just call back here and you
can get help.

Also I'm guessing that you haven't learned about function yet
(such as writing your own, passing data to and from them etc.)
Take a look at this as well.

I think that I have over complicted things with my loops.
I am getting 3 errors right now.

Code:

---

#include <iostream>
#include <stdlib.h>
#include <string>
#include <stdio.h>

using namespace std;

int main()
{
cout<<"Hello\n";
cout<<"Please enter your first name and press enter\n";

string name;

cin>> name;
//Clear screen:

system("cls");

cout<<"Now enter your age\n";

int age;

cin>> age;
system("cls"); /*Clears the screen*/
if (age < 1 ) {
    cout << name << ", you are not " << age << "\n";

}
else if (age > 124 ) {
    cout << name << ", you are not " << age << "\n";

}
else
{
cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";

if ( age < 12 && age > 0 ) {
    cout<<"You are a child!\n";
}
else if ( age >= 13 && age <= 19) {
    cout<<"You are a teenager\n";
}
else if ( age > 19 && age <= 55) {
    cout<<"You are an adult\n";
}
else
{
    cout<<"You are elderly\n";
}
}

cout<<"Is this right?\n";
string right;
cin>> right;

if (right == "no") {
while ( right == "no" ) {
    cout<<"Enter your age\n";
    cin>> age;
    system("cls"); /*Clears the screen*/
if (age < 1 ) {
    cout << name << ", you are not " << age << "\n";

}
else if (age > 124 ) {
    cout << name << ", you are not " << age << "\n";

}
else
{
    cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";

if ( age < 12 && age > 0 ) {
    cout<<"You are a child!\n";
}
else if ( age >= 13 && age <= 19) {
    cout<<"You are a teenager\n";
}
else if ( age > 19 && age <= 55) {
    cout<<"You are an adult\n";
}
else
{
    cout<<"You are elderly\n";
}
}
}
else if ( right == "yes") {
    cout<<"Ok, Press enter or Esc to exit\n";
    cin.get()
}
}
return 0;
}

---

Code:

---

if (right == "no") { /* Not necessary */
while ( right == "no" ) {

---

Yep, you've got a lot of syntax errors, I can tell just by running it through a syntax checker. However, I don't think it's the fault of adding a loop. You really need to adopt a cleaner coding style that is easier to read.

Code:

---

int main (void)
{
    if (condition)
    {
        do stuff;
        do this too;
        and this;
    }
    else
    {
        try this instead;
    }
    return 0;
}

---

In my psuedo-code you can tell by eyeballing where one code block ends and another begins.

You had a lot of code duplication there, no need. Here is your
code tweaked around a little and reformatted to be easier to
read:

Code:

---

#include <iostream>
#include <string>
#include <cstdlib>

using namespace std;

int main(){

        string right = "no";

        cout<<"Hello\n";

        while (right == "no"){
                cout<<"Please enter your first name and press enter\n";

                string name;
                cin>> name;
                system("cls");

                cout<<"Now enter your age\n";
                int age;
                cin>> age;

                system("cls");

                if (age < 1 ) {
                        cout << name << ", you are not " << age << "\n";
                }

                else if (age > 124 ) {
                        cout << name << ", you are not " << age << "\n";
                }

                else{
                        cout<<"So you are called "<< name <<" and you are "<< age <<" years old\n";

                        if ( age < 12 && age > 0 ) {
                                cout<<"You are a child!\n";
                        }

                        else if ( age >= 13 && age <= 19) {
                                cout<<"You are a teenager\n";
                        }

                        else if ( age > 19 && age <= 55) {
                                cout<<"You are an adult\n";
                        }

                        else{
                                cout<<"You are elderly\n";
                        }
                }

                cout<<"Is this right?\n";
                cin>> right;

                while ((right != "yes") && (right != "no")){

                        if ((right != "yes") && (right != "no")){
                                cout<<"Please enter yes or no\n";
                                cout<<"Is this right?\n";
                                cin>> right;
                        }
                }
        }

    cout<<"Ok, Press enter or Esc to exit\n";
    cin.get();

        return 0;
}

---

This should work for you, and I added a check to see whether
yes or no was not entered. The code should be fairly
straightforward to you now.

Thanks for helping me again.
I will try to write the code in a neater style and in all languages everyone knows that i am very messy. Thanks for the help. I see what you have done because at first I was wondering how it knew that the string called right was no but then I saw it being made at the very start. :D

I have another question but I don't want to make a new topic for it.
When defining variables you can use int for integers and string for "text"
The string variable can hold text (ie letters) and numbers but int can only hold numbers
Why would you want to use int.
Say i was asking for an age one person might type it in as a number like 12 but someone else might type in the actual word like twelve
Why would you want to use int instaed of string
Does string have any limitations in the program or is it just bad programing.

Well, programmers like to use data types responsibly. This kind of issue comes up because you always get input from the user in string format, and in order to have a real -number- a conversion must take place.

There are times when leaving numbers in string format is easier or best: like dates, or IP addresses, but for 90% of the time you want to store a number in a number type because:
- doing math is easy
- the number is represented in a compact format
- it's easier to check to see if the numerical data is an error itself, like your age program showed

One more thing - strings can handle numbers as well. For
example, you can declare a string variable and use it for a
numerical selection (1, 2, 398, 10 etc). The thing is, the string
data type handles characters - which themselves are a data
type (look up char somewhere). A string is merely a group of
characters.

The problem is, that if you used a string (or a single char), the
numbers you enter are in a completely different format than
if the data type was an integer. This is due to ASCII, the standard
encoding for characters. Characters are typically represented
internally by 1 byte (allowing for 0-255 unique values). The
problem lies with the fact that the equivalent ASCII "code" for
the number 0 doesn't start at 0 - it is 48 (obviously not the
direct binary equivalent).

This can cause all sorts of problems - such as performing math
operations, or even representing numbers with 2 digits or more.
So we have integers - which represent the numbers we enter in
their binary equivalent. We can do math operations and represent
numbers bigger than 9 using their direct binary equivalent.

There are also differences in performing comparisons,
assignments/initialisations, and so on. Take a look at this
brief example and not the highlighted difference. Run it and
see a huge difference in the output for the same number.

Code:

---

#include <iostream>
#include <string>

using namespace std;

int main (void)
{
        int a_num = 9;
        char a_char = '9';
        string a_string = "9";

        cout << a_num + a_num << endl;                //performing normal addition
        cout << a_char + a_char << endl;        //outputs sum of their decimal equivalent codes
        cout << a_string + a_string << endl;        //Results in appending one string onto another

        cin.get ();

        return 0;
}

---

Lastly, characters, integers and strings all have different sizes in
memory - as I said, a char is typically 1 byte, and string is actually
a class - which means that there is a lot more than meets the
eye - much larger than a char or an int.

Wow there is a huge difference in the numbers that it returned.
the int was right and said 18, I don't have a clue wat char did and string just added them together in a line instead of adding them

Well like i said, the integer is the best way to represent real
numbers (well it won't handle decimal fractions, but there's also
a float type, and a double type which handle them). The ASCII
value of character 9 is 57. This means the in binary, if the data
type is char, the 9 looks like 00111001. Adding it to itself
produces 114 which is actually the character 'r', but the decimal
equivalent value is outputted. Then with the strings, the + operator
appends one string onto another, resulting in a string containing
two characters - 9 and 9 (strings are groups of characters, remember?)