Why appear "#" added when copy chars in C - c

Question

I'm creating a program in C, which receive a file and reverses each line like this:
$ cat file
Line 1
Line 2!
Line_3
$ ./reverse < file
1 eniL
!2 eniL
3_eniL
But I get an error and I don't know why.
In the program, I made a loop which:
Read a line from stdin to a string of 2048 chars.
Get the strlen from the read line and made a new string.
Copy, char by char, the characters of the string to the new string, in reverse order.
But, running the program, sometimes copy a char and other simbols (#) getting something like this:
http://i.stack.imgur.com/G8VTx.png
Some strings get # simbols depending on the length. Here, another example:
http://i.stack.imgur.com/1UKdL.png
The files are in us-ansii.
The code of the program is:
#include <stdio.h>
#include <string.h>
#include <sysexits.h>
#include <stdbool.h>
int main(int argc, char *argv[]){
char string[2048];
bool final = false;
while(!final){
fgets(string,2048,stdin); // Read line
if(feof(stdin))
final=true;
else{
int length;
length = (string[strlen(string)-1] == '\n') ? strlen(string)-1 : strlen(string);
char reverseStr[length];
// Loop
int count = length;
for(int i=0;i<length;i++){
reverseStr[i]=string[count-1];
count--;
}
printf("%s\n",reverseStr);
}
}
}
I have tried changing the loop:
for(int i=0;i<length;i++){
reverseStr[count-1]=string[i];
count--;
}
Whit pointers:
for(int i=0;i<length;i++){
char * pr = $reverseStr[count-1];
*pr=string[i];
count--;
}
# Symbol use to appear in the same position.
"Febrero" gets "orerbeF"
"Febrerol" gets "lorerbeF#"
"Febreroll" gets "llorerbe#" (lose the "F")
Here an image of the gdb:
When program is reversing second line "Febreroll"
reverseStr is "llorer" (in $12)
In the next iteration:
reverseStr is "llorerb" (in $14)
In the next iteration, program copy an "e" and more things:
reverseStr is "llorerbe\221\b#" (in $16)
GDB IMAGE IN A COMENT↓↓↓

Answer 1

This occurs because the code does not take care to insure there is a NUL character at the termination. The # happens to appear in the (uninitialized) buffer at the end, then presumably a random NUL is after that.
To fix this, do something like:
for(int i=0;i<length;i++){
reverseStr[i]=string[count-1];
count--;
}
reverseStr[length] = '\000'; // I added this.

Answer 2

You have the length stored as a separate count rather than a NUL terminator. So use the length in the format string.
printf("%*s\n", length, reverseStr);