Need a little help with my project

First of all, I'd like to introduce myself to the C-Programming.com boards. I'm taking CS in college and not going to class for the summer made me rusty. If anyone can provide me with some insight with why I get errors when building this program, it would be helpful.

Code:

#include <cstring>
#include <iostream>
#include <cmath>
using namespace std;

void encode(char[] ,char[] ,char[] );

void main()
{
	char table[5][10];
	char statement[50];
	char keyword[10];

	cout<<"Please enter your statement,max 50 characters, all lowercase, with no spaces."<<endl;
	cin.get(statement,50);
	cout<<"Please enter your keyword. Do not repeat any letters.";
	cin>>keyword;
	
	cout<<"Our original statement is "<<statement<<endl;
	
	encode(statement,keyword,table);

	for (int y=0;y<strlen(keyword);y++)
		{				
		for (int x=0;x<ceil(strlen(statement)/strlen(keyword))+1;x++)
			{
			cout<<table[x][y];
			}
		cout<<' ';		
		}										
		
	cout<<endl<<endl;
	
}

void encode(char statement[], char keyword[], char table[])
{
	int i=0;
	int keylength = strlen(keyword);
	int messagelength = strlen(statement);

	for(int x=0;x<ceil(messagelength/keylength)+1;x++)		  
		for(int y=0;y<keylength;y++)	
		{
			table[x][y] = statement[i];
			i++;
		}
}

Thanks in advance. ^_^

>>#include <cstring>

wrong header... <string> for str functions (strlen)

for C-style strings it's <ctype>


>>encode(statement,keyword,table);

you need to speciy one of the dimensions of table...

encode (statement,keyword,table[x][]);

It would help if you give the errors your getting.

Just a few things I noticed:

1. int main( ), not void main( )
2. encode takes three char* args, but you pass it two char*s and a char** (table is a char**)

Cheers

Originally posted by major_small
>>#include <cstring>
wrong header... <string> for str functions (strlen)

<cstring> is right... <string> is the Std C++ Lib 'string' class.

oh really? I always used <string>... okey dokey then... ignore that one

Hmm... Kinda strange that it worked.

All right, I changed my function header to: void encode(char statement[], char keyword[], char table[5][])
and my function call to: encode(statement,keyword,table[5]);

however, this gives me another error:
'<Unknown>' Missing Subscript
and points to my function header before my function code.

Once again I am lost, and the way things are going, I'm going to be here alot more often this semester.

i guess so... I just compiled a program a few times with both headers, and there was no difference at all...

Hmm... right... The problem is you implemented both of our solutions. While table is a char**, table[x] (where x is 0, 1, ..., 4) is a char*. Based on the fact that the encode function actually uses both subscripts, I'd say your probably looking for just changing the function prototype to have a char**, and not using table[x] as a char*.

I apologize for my stupidity, but...wha?

My new semester's resolution is not to take the summer off of using C++.

Anyway, you lost me there.

Code:

#include <cstring>
#include <iostream>
#include <cmath>
using namespace std;

void encode(char[] ,char[] ,char**);

int main()
{
	char table[5][10];
	char statement[50];
	char keyword[10];

	cout<<"Please enter your statement,max 50 characters, all lowercase, with no spaces."<<endl;
	cin.get(statement,50);
	cout<<"Please enter your keyword. Do not repeat any letters.";
	cin>>keyword;
	
	cout<<"Our original statement is "<<statement<<endl;
	
	encode(statement,keyword,table[5]);

	for (int y=0;y<strlen(keyword);y++)
		{				
		for (int x=0;x<ceil(strlen(statement)/strlen(keyword))+1;x++)
			{
			cout<<table[x][y];
			}
		cout<<' ';		
		}										
		
	cout<<endl<<endl;

	return 0;
}

void encode(char statement[], char keyword[], char table[5][])
{
	int i=0;
	int keylength = strlen(keyword);
	int messagelength = strlen(statement);

	for(int x=0;x<ceil(messagelength/keylength)+1;x++)		  
		for(int y=0;y<keylength;y++)	
		{
			table[x][y] = statement[i];
			i++;
		}
}

That is exactly what I have right now.

Once again I apologize for my stupidity. Once I re-familirize myself with the language, I won't have any lapses like that.

here's one way to do it (the way I was talking about before):

Code:

#include <cstring>
#include <iostream>
#include <cmath>
using namespace std;

void encode(char*,char*,char*);

void main()
{
	char table[5][10];
	char statement[50];
	char keyword[10];

	cout<<"Please enter your statement,max 50 characters, all lowercase, with no spaces."<<endl;
	cin.getline(statement,50,'\n');
	cout<<"Please enter your keyword. Do not repeat any letters.";
	cin>>keyword;
	
	cout<<"Our original statement is "<<statement<<endl;
	
                for(int x=0;x<5;x++)
	          encode(statement,keyword,table[x][]);

	for (int y=0;y<strlen(keyword);y++)
		{				
		for (int x=0;x<ceil(strlen(statement)/strlen(keyword))+1;x++)
			{
			cout<<table[x][y];
			}
		cout<<' ';		
		}										
		
	cout<<endl<<endl;
	
}
...

that probably doesn't do what you want it to (I didn't look into encode), but it's just a prototype that you should be able to work off of... I would actually go with what Zach L. said, because I would tend to agree with him on this one...

I want to pass the entire 2D array "table" to the function.

What the function does is take the message, insert it into the table in row-major order. After this, the message is printed in column major order. The actual keyword is arbitrary, because the important part is the length of the keyword, as we do not have to sort the array. (originally, we had to sort the array and print it based on the alphabetical order of the letters in the keyword, but too many people were having trouble implementing this.)

Code:

#include <cstring>
#include <iostream>
#include <cmath>
using namespace std;

void encode(char[] ,char[] ,char[][10]);

int main()
{
	char table[5][10];
	char statement[50];
	char keyword[10];

	cout<<"Please enter your statement,max 50 characters, all lowercase, with no spaces."<<endl;
	cin.get(statement,50);
	cout<<"Please enter your keyword. Do not repeat any letters.";
	cin>>keyword;
	
	cout<<"Our original statement is "<<statement<<endl;
	
	encode(statement,keyword,table);

	for (int y=0;y<strlen(keyword);y++)
		{				
		for (int x=0;x<ceil(static_cast<double>(strlen(statement)/strlen(keyword)))+1;x++)
			{
			cout<<table[x][y];
			}
		cout<<' ';		
		}										
		
	cout<<endl<<endl;

	return 0;
}

void encode(char statement[], char keyword[], char table[][10])
{
	int i=0;
	int keylength = strlen(keyword);
	int messagelength = strlen(statement);

	for(int x=0;x<ceil(static_cast<double>(messagelength/keylength))+1;x++)		  
		for(int y=0;y<keylength;y++)	
		{
			table[x][y] = statement[i];
			i++;
		}
}

I get errors about ceil() being ambiguous, but I've never heard of ceil function before...


Edit: looked up ceil(), a simple cast fixed my errors...should compile fine now

Wow, that worked...well except for one thing:

I use the phrase "allyourbasearebelongtous" as my input and "movezig" as my keyword.

The output is:

Please enter your statement,max 50 characters, all lowercase, with no spaces.
allyourbasearebelongtous
Please enter your keyword. Do not repeat any letters.movezig
Our original statement is allyourbasearebelongtous
abbo laeu lsls yeo oan¨d urg¨d ret¨d

Press any key to continue

What are those weird symbols after the 5th 6th and 7th sets of letters and how can I rid myself of them?

Or more simply put, how do I initialize a character array so I don't get anything like that?

The weird symbols are because you don't initialize the contents of table and you don't fill it up all the way in encode. Your statement is 24 characters and your key is seven characters. So you have seven sets of letters and you add a letter to each set until you have added all 24 letters, but you leave the last four spots open. When you output the table you are outputting four letters per set, regardless of how many letters have been added to that set.

You could initialize table in the beginning using memset. If you set it to all 0's then you can check for a 0 in the table and stop outputting when you reach it. Or you could add a counter to stop outputting when the message length is reached. Or you could initialize to the ' ' (space) character and it will output spaces instead of gobbledy-gook.