Thread: Recursion help please?

  1. #1
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    Recursion help please?

    Hi everyone,

    I'm a newbie to c programming.... having trouble with recursion now....

    how do i write a recursive function that prints a positive integer in reversed order? for example: toReversed(345) will display 543.

    any tips to attempt doing recursive functions? what are the basic steps to do recursion? any tips for me to write out the algorithm?

    thanks everyone!

  2. #2
    Registered User Draco's Avatar
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    unless this is a homework assignment where you have to use it, recursion isn't the best way to do what you want. It would be worth it to look through the math and string function headers.

  3. #3
    Pursuing knowledge confuted's Avatar
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    try a while() loop...
    Away.

  4. #4
    ....
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    Perhaps this gives an impression of what you could do:

    345 % 10 = 5
    345 - 5 = 340
    340 / 10 = 34

    34 % 10 = 4
    34 - 4 = 30
    30 / 10 = 3

  5. #5
    Registered User zahid's Avatar
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    You may do it this way:

    Code:
    //Reverse function
    void preversed(int num)
    {
    int i;
                                                                                                                                 
    if(num >= 10 )
            {
            i = num%10;
            printf("%d",i);
            preversed(num/10);
            }
    else
            printf("%d",num);
                                                                                                                                 
    }
                                                                                                                                 
                                                                                                                                 
    
    int main()
    {
    int num;
    printf("Enter your number:");
    scanf("%d",&num);                 //Collect number
                                                                                                                                 
    printf("Number reversed  :");
    preversed(num);                    // Call the function
    printf("\n");
                                                                                                                                 
    return 0;
    }
    [ Never code before desk work ]
    -------------------------------------:-->
    A man who fears Nothing is the man who Loves Nothing
    If you Love Nothing, what joy is there in your life.
    =------------------------------------------------------= - I may be wrong.

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