Printing uppercase letters using 'if'

Question

What did I do wrong? I need this, to print all uppercase letters using 'if', but something is wrong because it is printing a letter more than once! Any help appreciated :)

//Uppercase letters using if;
#include<iostream>
using namespace std;

int main()
{
    char character='A';
label1:
if(character>='A')
    if(character>='Z')
        goto label2;
    else
    {
        cout<<character<<endl<<character++<<endl;
        goto label1;
    }

label2:
    cout<<"End"<<endl;
    return 0;
}

Welcome to Programmers. This is off-topic here and belongs on StackOverflow. Please don't re-ask it there as this can be migrated. A good rule to follow is if your question has you in front of your IDE it belongs on SO. If it has in front of a whiteboard it belongs on Programmers. Please take a moment to read the site's [FAQ] to learn more about asking question here. — Walter, Jan 05 '13 at 21:37
also WTH are you using goto? learn about loops and try not to use gotos they are almost **never** needed — ratchet freak, Jan 05 '13 at 21:42
@ratchetfreak: lol, I know about loops, but this is what the assignment said to use! — Ylli F, Jan 05 '13 at 21:47
Wait, you *have* to use goto instead of a proper loop? That's absurd! — chris, Jan 05 '13 at 21:48
Seriously, if they *make* you write code like this, get a new instructor/school/book/etc. — NPE, Jan 05 '13 at 21:52
@chris: If that's the level of tuition, this may be the only way forward! :) (nice word, BTW) — NPE, Jan 05 '13 at 21:54
If I had to use `goto`, I would name my label `http://stackoverflow.com/questions/46586/goto-still-considered-harmful`. — chris, Jan 05 '13 at 21:54
@All: Thanks; Just started C++ class from the ground(zero), we came down here so far, so he gave us this assignment "Print all uppercase letters using if(goto)" :( — Ylli F, Jan 05 '13 at 22:00
@chris: good one, it would even compile. in your `goto` statement you would have to replace `:` with `;`, but i guess it would not be that cumbersome if using `goto` is considered acceptable at all — Andy Prowl, Jan 05 '13 at 22:00
@AndyProwl, I have some "Cool features of C++" question on SO to thank for that, but I'm having trouble finding it! — chris, Jan 05 '13 at 22:01
@AndyProwl, There it was, a side link off of one I found on Google: http://stackoverflow.com/questions/75538/hidden-features-of-c?lq=1 — chris, Jan 05 '13 at 22:04

Andy Prowl · Accepted Answer · 2013-01-05T22:13:06.917

3

You increase the character variable twice. I am posting this answer just to show you what is the technical mistake, but there is a much bigger conceptual one, which is the use of goto. I suggest you to read some introductory book on C++.

//Uppercase letters using if;
#include<iostream>
using namespace std;

int main()
{
    char character='A';

label1:
if(character>='A')
    if(character>'Z'))
        goto label2;
    else
    {
        cout<<character<<endl;
        character++;
        goto label1;
    }

label2:
    cout<<"End"<<endl;
    return 0;
}

edited Jan 05 '13 at 22:13

answered Jan 05 '13 at 21:50

Andy Prowl

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Apparently the assignment requests him to use `goto`... `gofigure` – K-ballo Jan 05 '13 at 21:50
Still will never print "Z". – Hot Licks Jan 05 '13 at 22:03
It would have been sufficient to change `>=` to `>`. – Hot Licks Jan 05 '13 at 22:11
@HotLicks: true. i was just lazy to think too much, i thought the answer made the point clear enough – Andy Prowl Jan 05 '13 at 22:12

score 2 · Answer 2 · answered Jan 05 '13 at 21:49

2

The reason it's printing each letter more than once is the following:

    cout<<character<<endl<<character++<<endl;
          ^^^^^^^^^        ^^^^^^^^^

Each of the above would result in character getting written to cout.

answered Jan 05 '13 at 21:49

NPE

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score 2 · Answer 3 · answered Jan 05 '13 at 22:35

2

A bit late, but:

#include "stdafx.h"
#include<iostream>
#include <string>

using namespace std;

int main()
{
    string s("ABCDEFGHIJKLMNOPQRSTUVWXYZ");
    if (1) goto label1;
    cout << "End" << endl;
    return 0;
label1:
    cout << s << endl;
    return 0;
}

answered Jan 05 '13 at 22:35

Andrew Morton

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@Brad Thank you very much: I was sure I was going to get massively *down* voted. You gave me a good laugh there :) – Andrew Morton Jan 06 '13 at 00:06

exexzian · Answer 4 · 2013-01-05T22:16:54.173

1

Your code missed two points -

it was not printing Z
printing character two times cout<<character<<endl<<character++<<endl;

change: if(character>='Z') to -> if(character>'Z')

EDITED character++ ( that was typo) cout<<character<<endl<<character++<<endl; to -> cout<<character++<<endl;

edited Jan 05 '13 at 22:16

answered Jan 05 '13 at 22:04

exexzian

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the changes you mention are not enough, as it would never end up increasing `character`. it is also needed to add a `character++` after the `cout` statement. – Andy Prowl Jan 05 '13 at 22:10

Printing uppercase letters using 'if'

4 Answers4