C programming dilema

Propyro · Post by **Propyro** » Mon Oct 06, 2003 9:00 pm

ok, i'm stuck ... i've got three simple programs that need to be done by midnight.

The first problem is a program that will take a 5 digit number, isolate the digits, and add them together. The 5 digit number must be one variable though.

I can get the first digit easily ... jsut divide by 10000. but it's the other digits that are pissing me off because i can't seem to get the formula to work with a random 5 digit number. And i know this is easy but ... fucking hell i can't remember shit about programming any more.

second problem ... i have to make a time counter.

i input one time in 24 hour time and a second one in 24 hour time. then it tells me if they are valid times, and tells me teh difference between them.

The third probram is a number mirroring program. i give it a 3 digit number, then i give it anohter, and it will tell me if it is a mirror of the first number. (ie. is in revers order.) I can only use one variable for this.

man this sucks ... these are easy programs but i can't remember shit for the life of me. And yes, i was trying to get this stuff done while i was posting ... but i suck at programming despite how much i like it.

I'm not asking you to give me the code, but if you can give me a hand it would be nice.

[/|\]

Propyro · Post by **Propyro** » Mon Oct 06, 2003 9:09 pm

lol .. wheres danielWang when you need him ... god this sucks ...

[/|\]

madmag9999 · Post by **madmag9999** » Mon Oct 06, 2003 9:20 pm

problem 1:
u could take the number in as a string then do damn i forget what its called but there is a thing that makes it find the number in the specifided space of the string then u save it as a int and then repeat the process for all 5 numbers in the string then add them

madmag9999 · Post by **madmag9999** » Mon Oct 06, 2003 9:23 pm

problem 3:
also input it as a string then do what i said to do to the first one (find the numbers in the string and save them as int's) then add multiple the last int by 100 the second one 10 and leave the first one alone then add them and save them as a string then comepare the two strings

madmag9999 · Post by **madmag9999** » Mon Oct 06, 2003 9:27 pm

http://cplus.about.com/library/weekly/aa051202a.htm there is a nice little tutorial on strings for u so u can find out how to find the postion in the string. if i remember correctly its string positon something eh the tutorial should have it

dokidoki · Post by **dokidoki** » Mon Oct 06, 2003 9:29 pm

Are you allowed to convert them to strings or do you have to keep them as numbers?

An important operator for the first (and can be useful in the others) is the modulus/remainder ("mod") operator. It gives you the remainder of a division. It's represented by the percent sign. (%)

ie:
98 / 10 = 9
98 % 10 = 8

madmag9999 · Post by **madmag9999** » Mon Oct 06, 2003 9:30 pm

problem 2:
to find if they are valid u would need to divide the hours by 12 and if its <= 12 then its valid and the mintes by 60 and if its < 60 then its valid and then same for the seconds. then to compare them take time #1 and divide the hours by 60 then add it to the minutes and multply the seconds by 60 and add to the minutes do the same to time #2 then compare the two int's that u converted into minutes

Propyro · Post by **Propyro** » Mon Oct 06, 2003 9:58 pm

well i don't think weve gotten to strings yet in class, but if we could get it to wrok with strings then it's still ok. Also i forgot about the modulus function ... like i said ... insomnia is killing me ...

madmag wrote:problem 1:
u could take the number in as a string then do damn i forget what its called but there is a thing that makes it find the number in the specifided space of the string then u save it as a int and then repeat the process for all 5 numbers in the string then add them

i don't know, we haven't covered strings yet. But i'll read the tutorial.

[/|\]

Propyro · Post by **Propyro** » Mon Oct 06, 2003 10:12 pm

prehaps i should have mentioned that this is C, not C++, and if your giving me instructions in C++ there are soem thigns i might not beable to do, or the syntax might be wrong for me.

[/|\]

madmag9999 · Post by **madmag9999** » Mon Oct 06, 2003 10:18 pm

o yea ummmmm that would change alot. ill try to find a c tutorial for u sorry bout that