Interesting problem....reverse order of characters in a String!!!!

This is a discussion on Interesting problem....reverse order of characters in a String!!!! within the C Programming forums, part of the General Programming Boards category; Hey guys Im slowly starting to learn C and i was quite interested in this problem... If i entered a ...

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    Interesting problem....reverse order of characters in a String!!!!

    Hey guys Im slowly starting to learn C and i was quite interested in this problem...
    If i entered a line of characters say a sentence how would i be able to print out the reverse of the input. Eg
    Please enter string:
    I hate debugging.

    .gniggubed etah I (This is what the result should look like)

    Any ideas.....

  2. #2
    ATH0 quzah's Avatar
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    There are many ways to do it. Read one character at a time recursively. Read the entire line into a large buffer and walk backwards from the end. Give it a shot!


    Quzah.
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    Store it into an array and print the array backwards.

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    Jack of many languages Dino's Avatar
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    Quote Originally Posted by slowprogrammer View Post
    Eg
    Please enter string:
    I hate debugging.

    .gniggubed etah I (This is what the result should look like)

    Any ideas.....
    When I first saw this, I wanted to say it was wrong, but it's not. I was looking for

    .gniggudeb etah I

    But then the rest of the characters would have to be backwards too! (I guess the "i" already is) ho ho ho.
    Mac and Windows cross platform programmer. Ruby lover.

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    12/20: Mario F.:I never was, am not, and never will be, one to shut up in the face of something I think is fundamentally wrong.

    Amen brother!

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    C++まいる!Cをこわせ! Elysia's Avatar
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    A stack is a nice structure for reversing stuff.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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    Quote Originally Posted by slowprogrammer View Post
    Hey guys Im slowly starting to learn C and i was quite interested in this problem...

    Any ideas.....
    So interested that you want someone else to tell you how to solve the problem instead of attempting it on your own, then when stuck ask a specific question. I hope your school assignment isn't due too soon.

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    a little c++ here, but you can figure it out...
    Code:
    int main(){
    
    char text[255];
    int i=0;
    cout>>"press z to stop"<<endl;
    while(i<255 || ){// dont uverrun the buffer 
        char k;
         cin>>k;
         if(k =='z') break;
    }
    for( ; i >0; i--){
        cout<<text[i];
    }
    return 0;
    }

  8. #8
    C++まいる!Cをこわせ! Elysia's Avatar
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    Don't hand out solutions or the newbies will not learn anything! I urge you to read the Homework Policy.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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    Registered User claudiu's Avatar
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    Quote Originally Posted by smasherprog View Post
    a little c++ here, but you can figure it out...
    Code:
    int main(){
    
    char text[255];
    int i=0;
    cout>>"press z to stop"<<endl;
    while(i<255 || ){// dont uverrun the buffer 
        char k;
         cin>>k;
         if(k =='z') break;
    }
    for( ; i >0; i--){
        cout<<text[i];
    }
    return 0;
    }
    1) Stop providing complete solutions

    2) Stop writing C++ code on the C forum

    3) Stop living with the impression that C and C++ are similar so it doesn't really matter which one you use

    4) Stop assuming that the input will not contain the letter 'z'
    Last edited by claudiu; 05-04-2010 at 12:04 PM.
    1. Get rid of gets(). Never ever ever use it again. Replace it with fgets() and use that instead.
    2. Get rid of void main and replace it with int main(void) and return 0 at the end of the function.
    3. Get rid of conio.h and other antiquated DOS crap headers.
    4. Don't cast the return value of malloc, even if you always always always make sure that stdlib.h is included.

  10. #10
    ATH0 quzah's Avatar
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    5) What is that while loop's OR supposed to be doing?


    Quzah.
    Hope is the first step on the road to disappointment.

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    How about using string.length() and a for loop to reverse it? C++ is cool, it's quite amazing what you can get to work with just playing with it!

  12. #12
    ATH0 quzah's Avatar
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    If we wanted C++, we'd be on the C++ forum.


    Quzah.
    Hope is the first step on the road to disappointment.

  13. #13
    Registered User claudiu's Avatar
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    Quote Originally Posted by fadlan12 View Post
    How about using string.length() and a for loop to reverse it? C++ is cool, it's quite amazing what you can get to work with just playing with it!
    The same can be said about C and probably most languages.
    1. Get rid of gets(). Never ever ever use it again. Replace it with fgets() and use that instead.
    2. Get rid of void main and replace it with int main(void) and return 0 at the end of the function.
    3. Get rid of conio.h and other antiquated DOS crap headers.
    4. Don't cast the return value of malloc, even if you always always always make sure that stdlib.h is included.

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    Whoops, sorry about that. Was not trying to down any other languages.

  15. #15
    ATH0 quzah's Avatar
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    It's not your fault, you didn't bring up C++ on the C forum.

    That said, we'd like to hear from the OP again. Show us what you've got slo-pro!


    Quzah.
    Hope is the first step on the road to disappointment.

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