Anyone know what this means?

i found this encryption code online but i'm not as advanced as the code is so can someone explain to me what is going on in this section. i have included the part of the code i didn't understand.

code-

void decrypt(char *daf)//the decrypting function
{
int decr; //the main int
char x; //the input char

ifstream in; //input stream
ofstream out; //output stream

in.open(daf);//open the inout stream
if(in.fail())
{//see if it's not there
cout<<"Error couldn't open the IN file\n";//print
cout<<"Press \"m\" to return to main menu";
return;//quit
}//END OF IF

cout<<"Enter the OUT file name: ";//ask for the out filename
cin>>daf;//get it
out.open(daf);//open the outfile
in.get(x);//get the input char

if( in.eof() )//IF READING END OF FILE
{
return;//quit
}//END OF IF

while(x!=EOF)
{//while x is not beyond end of file
decr=x+0xFACA;//the dectypring
out<<(char)decr;//print
in.get(x);//get the next char

if(in.eof())//if read beyong the eon of file
break;//break
}//END OF WHILE

return;
}//END OF DECRYPT

i don't understand what the line decr=x+0xFACA means. when i typed the 0xFACA into my program it turned into a special font. not the font of a reserved word, just a different font from the other text. the encryption function is the same as the above line except it says x-0xFACA. any help would be appreciated.

thanks all

1. Use the code tags when posting code......as everyone says around here......it's very hard to read code when it's not code, just a bunch of letters*not all of that, but use the friggin' code tags*

2. The little 0xfca or whatever is a charecter identifier in hexidemal. Don't bother typing that in......