I need a little help starting this...

This is a discussion on I need a little help starting this... within the C Programming forums, part of the General Programming Boards category; I've just recently started programming with C at college and I've been given a problem that has me stumped. 6. ...

  1. #1
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    I need a little help starting this...

    I've just recently started programming with C at college and I've been given a problem that has me stumped.

    6. Write a program to determine whether the sum of digits of a three digit input number is even or odd. The input may have less than 3 digits, but never more. For instance, the sum of digits of 145 is 1+4+5. The answer is 10 which is even. Your program should first sum the digits and then determine whether this sum is even or odd. USE A LOOP STRUCTURE TO SEPARATE THE DIGITS AND ADD THEM.

    How would I even go about starting this problem? Thanks for any help.

  2. #2
    Fear the Reaper...
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    Any 3 digit number can be written as :

    a*10^2 + b*10^1 + c*10^0

    Let's call this number m. Now notice that :

    m mod 10 = c
    m mod 100 = b*10 + c
    m mod 1000 = c*100 + b*10 + c

    Noticing a pattern yet ?
    Teacher: "You connect with Internet Explorer, but what is your browser? You know, Yahoo, Webcrawler...?" It's great to see the educational system moving in the right direction

  3. #3
    and the hat of wrongness Salem's Avatar
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    Discover what 145 % 10 does, and what 145 / 10 does.
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