Word unscrambling

**pukebucket** · 01-07-2006

Well the file is large so I found the largest one I could (12 charectors) but said 15 to be sure. Sorry if this complicates things I didn't realise how important it is. I though it was like when you declare integers larger then you need to prevent overflows.

No we haven't studied letter frequency counter.

Thanks again.

**treenef** · 01-07-2006

The reason why the length of the largest word to be unscrambled is important is due to the time complexity problem.

If you are using a brute force, i.e a permutation generator then a word with 12 letters in it would take a long time to solve.

Whereas, with a letter frequency counter can solve any word of any length.

**pukebucket** · 01-07-2006

I see. So this means that my program will take along time to solve all ten?

**Queatrix** · 01-07-2006

>> I see. So this means that my program will take along time to solve all ten?

That totaly depends.

**treenef** · 01-07-2006

Yes, since if you use a permutation generator, then by its very nature you are using a brute force algorithm.

The concept of Letter Frequency counting is explained here:

http://www.codeproject.com/cpp/Jumble.asp

Which is initially where I got my idea to create an efficient word unscrambling utility.

**pukebucket** · 01-07-2006

Ok. From one of your previous posts, you said to use

Code:

char word[MAX_WORD_SIZE][FILE_SIZE];
ifstream b_file;
int i;
for(i =0; i < FILE_SIZE; i++)
b_file.in >> word[i];

This is what I think each line means.

First line - Declare a char variable with the size of the largest word and the size of the file with the unscrambled words (i think)

second line - Open the unscramble file
third line - declare i as an integer variable
fourth line - Set i as o, as long as i is smaller then the file size, increase i by 1 each loop
fifth - Not sure. I think it sets the variable "word" to read the next string every loop. Is that right?

P.S - Thanks treenef

I'll read this page through and hopefuly understand it.

**treenef** · 01-07-2006

char word[MAX_WORD_SIZE][FILE_SIZE];

Do you have to use char arrays or string literals?

***If you have any problems post them here. I've done this before.

What I'd recommend is you read that link and think about a solution to your problem. When you have given it enough thought. Come back here.

Reading files in and out is not a problem. Worry about that later.

**pukebucket** · 01-07-2006

Thank you so much

This page looks very useful. He didn't specify how to do it, he just told us to do how ever we want :S

I'll do as you said and come back if I need more help. Once again, thank you so much it really is alot to me.

**pukebucket** · 01-07-2006

I've run into a problem. At

Code:

for (vai = all->begin(); vai != all->end(); vai++, cnt++)			
cout << cnt + 1 << " " << *vai << endl;			
char *strcpy ( char ans, const char *vai );                             
ofstream a_file ( "answer.txt", ios::app );
a_file<< *vai <<",";
a_file.close();

it messes up. I tried to make it write the answers to the text file, but it always ends up being squares. I think it's becuase it's writing the memory address to the file so I tried writing vai without the asterix. But it wont compile. Does anyone know why?
Thanks in advance

**treenef** · 01-07-2006

Just hang on a minute there.

Don't use the code from my link. It's perhaps a little too complicated for you anyway.

What I wanted you to do was actually read the concept behind a letter frequency counter.

Here's what you need to think about.

Let's say I give you a word:-

Code:

treenef

I want you to write a program which will spits out the letter frequency count for a specific word.

So...

Code:

t = 1
r = 1
e =3
n =1
f  =1

And as I've said before don't worry about file input/output until we've finished this.

**pukebucket** · 01-07-2006

No wait, I didn't copy it. I read the whole thing, and got an understanding of it and then tried to make his one do what my one has to do. His one couldn't write it to a file. I am not going to use his one trust me, my tutor would notice

and I would learn nothing from it. I simply want to know how it would write to a file.

**treenef** · 01-07-2006

Good, don't use that code.

I said worry about file input/output later...

but here's a link anyway
http://www.cprogramming.com/tutorial/lesson10.html

**pukebucket** · 01-07-2006

Originally Posted by treenef

Good, don't use that code.

I said worry about file input/output later...

but here's a link anyway
http://www.cprogramming.com/tutorial/lesson10.html

That's what I was reading!

**treenef** · 01-07-2006

never mind about that think about the letter frequency counter...

What have you got?

Code:

#include <iostream>

using namespace std;

int main()
{
    char array[100]="treenef";
    
    cout<<array[0];
    cout<<array[1];
    
    //letter count prog goes here
    
    cin.get();
    return 0;
}