First character not being printed?

[Willseph]

Hi everyone, I'm writing a project for college that requires us to translate an input file (read directly using the < unix symbol, not in the program itself) char-by-char using a translation table. I pretty much have it all done, but I'm running into a rather strange problem. Here's my code:

#include <iostream>
#include <iomanip>
#include <string>
#include <fstream>
using namespace std;
int main()
{
	ifstream keyFile("key.txt");
	string key;
	getline(keyFile,key);
	string curLine;
	while(getline(cin, curLine))
	{		
		int lineLength = curLine.length();
		char decrypted[lineLength];
		for( int i=0; i < lineLength; i++)
		{
			char current = curLine.at(i);	
			if(!((current>=97 && current <=122) || (current>=65 && current <=90)))
			{
				decrypted[i] = current;
				continue;
			}
			bool lowercase = current>=97 && current <=122;
			if(lowercase) current-=32;
			char real = key.find_first_of(current, 0)+65;
			if(lowercase) real+= 32;
			decrypted[i] = real;
		}
		cout << decrypted << endl;
	}
}

Everything works, and to test everything else I'm just using the alphabet for the key. However, with an input file containing:

Lorem ipsum
dolor
Sit Amet

I get the following printed out:

_orem ipsum
dolor
Sit Amet

(It's not actually a _ character, but rather a space).

For some reason, it seems to be replacing the very first character with a space or some other "blank" character. I thought maybe it's a problem in the decrypted[] array, but I printed decrypted[0] and it printed the missing L just fine. So if there's nothing wrong with the array itself, why is it not printing with the cout command?

[Willseph]

UPDATE

I tried a different input file to see if I would get the same problem, and I actually got something much stranger. The input was:

THIS
IS
MY
TEST
FILE

The output was:

 HIS
u
u
 EST
FILE

What's even more concerning is that after re-compiling and testing again with the same input file, I got this:

 HIS
Þ
Þ
 EST
FILE

What could be causing this?

[rocketboy9000]

You never initalized decrypted.

[Willseph]

Did I not on line 15?
char decrypted[lineLength];

[sohguanh]

char decrypted[lineLength];

Above only say you reserve space for variable decrypted. But the contents inside each space is not initialized yet.

[coder777]

What compiler do you use? line 15 is normally not allowed in C++.

[Willseph]

I'm... not sure, I'm using PuTTY to connect to my university's unix environment, but the compiler executable is called c++. How should this be initialized?

[sohguanh]

You can use the easy way memset(decrypted,0,lineLength) C string function.

[coder777]

My compiler (visual C++) complains about line 15. It's supposed to be char *decrypted = new char[lineLength]; (don't forget to delete it when you're done with it)

to initialize it with 0: memset(decrypted, 0, lineLength * sizeof(char)); but that's not supposed to be your problem since (as far as i see) you initialize it in your loop

line 30 is a problem if you don't have a 0 at the end of your string

[sohguanh]

string curLine = "Hello World!\n";
int lineLength = curLine.length();
char decrypted[lineLength];

Above compile fine for me using g++ version 3.4.6 20060404 (Red Hat 3.4.6-10)

[Willseph]

Thanks for the help so far guys, but I'm still having issues. I tried using memset but I don't think it can find where it's defined. I even included stdio.

I did, however, take coder777's advice and made the char *decrypted = new char[lineLength]; change and I delete it after every loop, but the problem still remains. Another test sample:

Input

ABCDEF GHIJKLMNO PQRSTUVW XYZ .,;' 0192837465
THfdf sfiwf HDHDFD

abcdefghijklmnopqrstuvwxyz

t

g
g
y
D
EE
C
T
t

.,
!~ 

Output

0BCDEF GHIJKLMNO PQRSTUVW XYZ .,;' 0192837465
0Hfdf sfiwf HDHDFD
0
DEF G0ghijklmnopqrstuvwxyz
0
0
0
0
0
0
0
0E
0
0
0
0
0,
!~ 

I'll have to work on it more tomorrow.

[rocketboy9000]

memset is in string.h.

[filipe]

In C++ that's <cstring>.