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Strings this time

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Strings this time

Mar 7th, 2008

Good day yet again ladies and gents. Today I'm having problems with strings and such. I've been tasked with creating fixed char arrays to contain first name, last name, and middle name. I've managed that, and have the calls in my main. I'm also tasked with using strlen (specifically) to find the length of the strings to create a dynamic array to hold all three names. This is where I'm running into problems. the first cpp file I'll post has the original functions for entering the names into the strings. The commented out portion was where I was getting the link individually (which works), but I am trying to write a separate function in another cpp file which keeps giving me linking errors. I'm not sure where they are coming from since I already used the extern keyword in the header. I'm sure it's possible to write a separate function in a separate cpp file, but am I making more trouble than it's worth? Here are the files:

Header

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#ifndef NAMEINP_H
#define NAMEINP_H
 
const int maxin = 16;
 
extern char lastName[maxin];
 
extern char firstName[maxin]; 
 
extern char midName[maxin];
 
char getlast( char lastName[] , int maxin);
 
char getfirst( char firstName[] , int maxin);
 
char getmid( char midName[] , int maxin);
 
//void displayName (char * name);
 
#endif
#ifndef NAMEINP_H
#define NAMEINP_H

const int maxin = 16;

extern char lastName[maxin];

extern char firstName[maxin]; 

extern char midName[maxin];

char getlast( char lastName[] , int maxin);

char getfirst( char firstName[] , int maxin);

char getmid( char midName[] , int maxin);

//void displayName (char * name);

#endif

Here are the functions

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#include "nameinp.h"
#include <iostream>
#include <string.h>
using namespace std;
 
//Input last name
char getlast( char lastName[] , int maxin)
{
	cout << " Please enter your last name up to 15 characters " << endl;
	cin.getline(lastName, maxin, '\n' );
	//size_t lastLen;
	//lastLen = strlen(lastName);
	//cout << lastLen << endl;
	return 0;
}
 
 
//Input first name
char getfirst( char firstName[] , int maxin)
{
	cout << " Please enter your first name up to 15 characters " << endl;
	cin.getline(firstName, maxin, '\n' );
	//size_t firstLen;
	//firstLen = strlen(firstName);
	//cout << firstLen << endl;
	return 0;
}
 
 
//Input middle name
char getmid( char midName[] , int maxin)
{
	cout << " Please enter your middle name up to 15 characters " << endl;
	cin.getline(midName, maxin, '\n' );
	//size_t midLen;
	//midLen = strlen(midName);
	//cout << midLen << endl;
	return 0;
}
#include "nameinp.h"
#include <iostream>
#include <string.h>
using namespace std;

//Input last name
char getlast( char lastName[] , int maxin)
{
	cout << " Please enter your last name up to 15 characters " << endl;
	cin.getline(lastName, maxin, '\n' );
	//size_t lastLen;
	//lastLen = strlen(lastName);
	//cout << lastLen << endl;
	return 0;
}


//Input first name
char getfirst( char firstName[] , int maxin)
{
	cout << " Please enter your first name up to 15 characters " << endl;
	cin.getline(firstName, maxin, '\n' );
	//size_t firstLen;
	//firstLen = strlen(firstName);
	//cout << firstLen << endl;
	return 0;
}


//Input middle name
char getmid( char midName[] , int maxin)
{
	cout << " Please enter your middle name up to 15 characters " << endl;
	cin.getline(midName, maxin, '\n' );
	//size_t midLen;
	//midLen = strlen(midName);
	//cout << midLen << endl;
	return 0;
}

Here is the function I'm trying to write that's giving me the hassles

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#include "nameinp.h"
#include <iostream>
#include <string.h>
using namespace std;
 
//Calculate the String Lengths
 
size_t totallength (size_t)
{
	size_t fullength = 0;
 
	size_t lastLen;
	lastLen = strlen(lastName);
	cout << lastLen << endl;
 
	size_t firstLen;
	firstLen = strlen(firstName);
	cout << firstLen << endl;
 
	size_t midLen;
	midLen = strlen(midName);
	cout << midLen << endl;
 
	fullength = lastLen + firstLen + midLen;
 
	return 0;
}
#include "nameinp.h"
#include <iostream>
#include <string.h>
using namespace std;

//Calculate the String Lengths

size_t totallength (size_t)
{
	size_t fullength = 0;

	size_t lastLen;
	lastLen = strlen(lastName);
	cout << lastLen << endl;
	
	size_t firstLen;
	firstLen = strlen(firstName);
	cout << firstLen << endl;

	size_t midLen;
	midLen = strlen(midName);
	cout << midLen << endl;

	fullength = lastLen + firstLen + midLen;

	return 0;
}

Okay, what am I screwing up? Thank you

Last edited by Ancient Dragon; Mar 7th, 2008 at 8:46 pm. Reason: correct code tags

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Re: Strings this time

Mar 7th, 2008

Okay, not sure why that posted as text instead of code

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Re: Strings this time

Mar 7th, 2008

Wow, no one after an hour? Is it that hard or did I just mess it up that badly?

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Re: Strings this time

Mar 7th, 2008

>>Wow, no one after an hour? Is it that hard or did I just mess it up that badly
I was naping

function totallength()
The parameter must have a variable name, you can't just put a data type without a variable named. Variable names can be omotted ONLY in function prototypes.

line 26: why did you bother to calculate the total length then turn around and toss the answer into the bit bucket by returning 0 ?

You also need to add 1 for the new string's null terminating character.

You could reduce that entire function to just one line

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size_t totallength()
{
   return strlen(firstname) + strlen(midname) + strlen(lastname) + 1;
}
size_t totallength()
{
   return strlen(firstname) + strlen(midname) + strlen(lastname) + 1;
}

Last edited by Ancient Dragon; Mar 7th, 2008 at 8:55 pm.

Don't PM me with questions -- you might get a nasty PM in response. If you have a question then post it in one of the forums.

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Re: Strings this time

Mar 7th, 2008

Thank you yet again AD, now for the next question. I'm having trouble getting the syntax right for the "new" string. I'm also unsure how to copy the other strings into it. I'd post what I did, but I seem to have become frustrated and dumped it..lol. What I did have for the new string was this

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char  *fullName = new char fullName [];
char  *fullName = new char fullName [];

but that gave me a list of errors, so I tried this

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 char  *fullName = new char[];
 char  *fullName = new char[];

Now this one seems to work, (compiles) but does it do what I want it to do?

I thought of just following it up with some lines such as this:

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char strcopy (char fullName, const char lastName);
char strcat (char fullName, ' ');
char strcat (char fullName, const char firstName);
char strcat (char fullName, ' ');
char strcat (char fullName, const char midName);
char strcopy (char fullName, const char lastName);
char strcat (char fullName, ' ');
char strcat (char fullName, const char firstName);
char strcat (char fullName, ' ');
char strcat (char fullName, const char midName);

First of all, I don't know if that works because I'm pretty ignorant about this to begin with, and second, the ' ' are supposed to be spaces but I'm sure that's not how they'll come out. I'm not sure how to do spaces with a strcat

Once I have that much working I have to figure if there is a way to automatically allocate the correct number of elements (using the strlength you helped me with earlier) and displaying the output of the above function showing the full name

Last edited by henpecked1; Mar 7th, 2008 at 11:25 pm.

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Re: Strings this time

Mar 7th, 2008

>>char *fullName = new char[];
You didn't tell new operator how many characters to allocate. put a number (or int variable name) between those square brackets.

Here's how to copy the strings

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strcpy( fullName, lastName);
strcat( fullName, " ");
strcat( fullName, firstName);
// etc etc like above
strcpy( fullName, lastName);
strcat( fullName, " ");
strcat( fullName, firstName);
// etc etc like above

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Re: Strings this time

Mar 7th, 2008

Okay, I understand telling it what to expect, but how do I pull that value from the size_t totallength function? do I do this?

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char *fullname = new char[totallength]
char *fullname = new char[totallength]

So it now looks like this?

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char  *fullName = new char[]; // with the box filled in
 
	strcopy (fullName, lastName);
	strcat (fullName, " ");
	strcat (fullName, firstName);
	strcat (fullName, " ");
	strcat (fullName, midName);
char  *fullName = new char[]; // with the box filled in

	strcopy (fullName, lastName);
	strcat (fullName, " ");
	strcat (fullName, firstName);
	strcat (fullName, " ");
	strcat (fullName, midName);

as that stands it gives me a load of errors about too many initializers and missing type specifiers....is that because the array box is empty?

Last edited by henpecked1; Mar 7th, 2008 at 11:38 pm.

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Re: Strings this time

Mar 8th, 2008

>>but how do I pull that value from the size_t totallength function? do I do this?

Define a variable to receive the value returned by that function

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size_t len = totallength();
char* fullName = new char[len];
size_t len = totallength();
char* fullName = new char[len];

>>char *fullName = new char[]; // with the box filled in

That is STILL wrong!

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Re: Strings this time

Mar 8th, 2008

I was just reading the part about setting the variable when I opened up the post. Now for the new array, do all the strcpy and strcats go in {} braces?