Reversed Integer Using Arrays, My friend told me its to complicated
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# Thread: Reversed Integer Using Arrays, My friend told me its to complicated

1. Member
Join Date
Sep 2009
Posts
37

## Reversed Integer Using Arrays, My friend told me its to complicated

The assignment everyone has done before..lol...reversing digits. How do i make my code more simple (as my friend stated)?

Trying to write a program that reverses the digits in an integer. Assuming that the max value of the integer is 99999. And using arrays to solve the problem.

For example if integer:
0 was entered, output is 0
10 was entered, output is 1
12 was entered, output is 21
123 was entered, output is 321
7600 was entered, output is 67
8015 was entered, output is 5108
90000 was entered, output is 9

here is my code:

Code:
```#include <stdio.h>
#include <math.h>

int main()
{
int intnumber, condition, remainder;
int counter = 0, i = 0, j = 0, counter1 = 0;
int reverseint[99999];

printf("Enter an integer number: ");
scanf_s("%d", &intnumber);
condition = intnumber;

while (condition > 0)
{
condition  = condition /10;
counter = counter + 1;
counter1 = counter1 + 1;
}

counter = counter - 1;
printf("The number in reverse: ");
while (counter >= 0)
{
remainder = intnumber % (int) pow(10, counter);
intnumber = intnumber/(int) pow(10,counter);
reverseint[i] = intnumber;
i++;
intnumber = remainder;
counter = counter - 1;
}

for(j=counter1-1;j >= 0;j--)
{
printf("%d ", reverseint[j]);
printf("\n");
}
}```

2. Elite Member Power Poster
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## Re: Reversed Integer Using Arrays, My friend told me its to complicated

Are you required to manipulate it *as* an integer? Because it would be much simpler to do it while it's still a string:
Code:
```    string valstr;
cin >> valstr;
std::reverse(valstr.begin(),valstr.end());
int val;
istringstream strm(valstr);
strm >> val;
cout << val;```
Of course, that's without input validation. The conversion from string to int prior to output is there solely to eliminate any leading 0s. This could be done in string form instead if desired.

3. Member
Join Date
Sep 2009
Posts
37

## Re: Reversed Integer Using Arrays, My friend told me its to complicated

Thanks! but

I found out that, I can't use printf but instead use couts.
I'm in a beginner level's C++ class and my teacher also wants it more simpler..aha

said i can't use scanf_s, pow, and strings!?!?!

4. Elite Member Power Poster
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Location
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## Re: Reversed Integer Using Arrays, My friend told me its to complicated

There's almost a one-to-one mapping between what you can do with printf/scanf and what you can do with cout/cin. That should be fairly trivial to convert.

You shouldn't need pow. Consider the algorithm in this sense:

You have two integers
8765
1234
and you want to modify them so that you will instead have
87654
123
How would you do this?

Then simply take that one step and put it in a loop. Even arrays are unnecessary.

5. Member
Join Date
May 2004
Posts
113

## Re: Reversed Integer Using Arrays, My friend told me its to complicated

For simplicity, I ignore error handling.

Code:
```int reverse(int n)
{
assert(n >= 0);

int result = 0;
while (n > 0)
{
int r = n % 10;
n /= 10;
result = result * 10 + r;
}

return result;
}```

6. ## Re: Reversed Integer Using Arrays, My friend told me its to complicated

Jim_King_2000: Please read the forum rules on doing homework for other people !!! People here are trying to help, your post was the opposite of helpful!

7. Member
Join Date
May 2004
Posts
113

## Re: Reversed Integer Using Arrays, My friend told me its to complicated

Originally Posted by treuss
Jim_King_2000: Please read the forum rules on doing homework for other people !!! People here are trying to help, your post was the opposite of helpful!
What's wrong with my post? Can't my code work?
By the way, would please provide the like to the forum rules? I can't find it.

Thanks,
Jim

8. Elite Member Power Poster
Join Date
Apr 1999
Posts
27,449

## Re: Reversed Integer Using Arrays, My friend told me its to complicated

Originally Posted by Jim_King_2000
By the way, would please provide the like to the forum rules? I can't find it.
Not rules, but guidelines that have been placed here and have been known for at least 10 years now.

http://www.codeguru.com/forum/showthread.php?t=366302

Regards,

Paul McKenzie

9. Member
Join Date
May 2004
Posts
113

## Re: Reversed Integer Using Arrays, My friend told me its to complicated

Originally Posted by Paul McKenzie
Not rules, but guidelines that have been placed here and have been known for at least 10 years now.

http://www.codeguru.com/forum/showthread.php?t=366302

Regards,

Paul McKenzie
I read the guidelines. Thank you.

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