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Help With Simple Program

hpardo11 (6)
I need to create a simple program that takes a phrase and scrambles the letters all up and or unscrambles them. I need to use simple functions and have pretty much completed it but I cannot get my functions to actually go forth and complete what they need to do. The code below will help you understand more of what I need it to do.

The program compiles fine but the spaces where the function output should be are blank. What am I doing wrong?

Header File
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#include <iostream>
#include <string> //for strings
#include <fstream> //for ifstream and ofstream

using std::string; //using standard lib and string

void encrypt( string input ); //helper encrypt function
void decrypt( string input ); //helper decrypt function

void encryptDecrypt( string inputfile, string outputfile ); //principle function declaration


Actual CPP
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#include "encrypt.h" //header file
#include <iostream>
#include <string> //for strings
#include <fstream> //for file stream, ofstream and ifstream

using std::endl;
using std::string;
using std::ifstream;//input file stream
using std::ofstream;//output file stream
using std::getline; //reading rest of the line

int main()//main test function
{
    encryptDecrypt( "inputED.txt", "outputEncDec.txt");//test input files
    return 0;
}

void encryptDecrypt(string inputfile, string outputfile) //principle function
{
    ifstream in(inputfile);  //input file
    ofstream out(outputfile);//output file

	string command, command2;
	in >> command;getline( in, command2); //simple extraction, then reading rest of line with loop

		while ( !in.fail() ) //input controlled failure loop
	{
        if ( command == "encrypt" )
        { 
		out << "encrypted:"; encrypt( command2 ); out << '\n';
		}
		else if ( command == "decrypt")
		{
		out << "decrypted:"; decrypt( command2 ); out << '\n';
		}
		
		in >> command; getline( in, command2 );
	}
	
    in.close();
    out.close();
}

void encrypt( string input ) //"helper" encrypt function
{
	string results = "";
	for ( int i=0; i<input.length(); i++ )
{
    if ( input[i] == 'a' )
		{
        results = results + "z";
		}
	else if ( input[i] == 'b' )
	{
		results = results + "y";
	}
	else if ( input[i] == 'c' )
	{
		results = results + "x";
	}
	else if ( input[i] == 'd' )
	{
		results = results + "w";
	}
	else if ( input[i] == 'e' )
	{
		results = results + "v";
	}
	else if ( input[i] == 'f' )
	{
		results = results + "u";
	}
	else if ( input[i] == 'g' )
	{
		results = results + "t";
	}
	else if ( input[i] == 'h' )
	{
		results = results + "s";
	}
	else if ( input[i] == 'i' )
	{
		results = results + "r";
	}
	else if ( input[i] == 'j' )
	{
		results = results + "q";
	}
	else if ( input[i] == 'k' )
	{
		results = results + "p";
	}
	else if ( input[i] == 'l' )
	{
		results = results + "o";
	}
	else if ( input[i] == 'm' )
	{
		results = results + "n";
	}
	else if ( input[i] == 'o' )
	{
		results = results + "l";
	}
	else if ( input[i] == 'p' )
	{
		results = results + "k";
	}
	else if ( input[i] == 'q' )
	{
		results = results + "j";
	}
	else if ( input[i] == 'r' )
	{
		results = results + "i";
	}
	else if ( input[i] == 's' )
	{
		results = results + "h";
	}
	else if ( input[i] == 't' )
	{
		results = results + "g";
	}
	else if ( input[i] == 'u' )
	{
		results = results + "f";
	}
	else if ( input[i] == 'v' )
	{
		results = results + "e";
	}
	else if ( input[i] == 'w' )
	{
		results = results + "d";
	}
	else if ( input[i] == 'x' )
	{
		results = results + "c";
	}
	else if ( input[i] == 'y' )
	{
		results = results + "b";
	}
	else if ( input[i] == 'z' )
	{
		results = results + "a";
	}
	}
}

void decrypt( string input ) //"helper" decrypt function
{
	string results = "";
	for ( int i=0; i<input.length(); i++ )
{
    if ( input[i] == 'z' )
		{
        results = results + "a";
		}
	else if ( input[i] == 'y' )
	{
		results = results + "b";
	}
	else if ( input[i] == 'x' )
	{
		results = results + "c";
	}
	else if ( input[i] == 'w' )
	{
		results = results + "d";
	}
	else if ( input[i] == 'v' )
	{
		results = results + "e";
	}
	else if ( input[i] == 'u' )
	{
		results = results + "f";
	}
	else if ( input[i] == 't' )
	{
		results = results + "g";
	}
	else if ( input[i] == 's' )
	{
		results = results + "h";
	}
	else if ( input[i] == 'r' )
	{
		results = results + "i";
	}
	else if ( input[i] == 'q' )
	{
		results = results + "j";
	}
	else if ( input[i] == 'p' )
	{
		results = results + "k";
	}
	else if ( input[i] == 'o' )
	{
		results = results + "l";
	}
	else if ( input[i] == 'n' )
	{
		results = results + "m";
	}
	else if ( input[i] == 'l' )
	{
		results = results + "o";
	}
	else if ( input[i] == 'k' )
	{
		results = results + "p";
	}
	else if ( input[i] == 'j' )
	{
		results = results + "q";
	}
	else if ( input[i] == 'i' )
	{
		results = results + "r";
	}
	else if ( input[i] == 'h' )
	{
		results = results + "s";
	}
	else if ( input[i] == 'g' )
	{
		results = results + "t";
	}
	else if ( input[i] == 'f' )
	{
		results = results + "u";
	}
	else if ( input[i] == 'e' )
	{
		results = results + "v";
	}
	else if ( input[i] == 'd' )
	{
		results = results + "w";
	}
	else if ( input[i] == 'c' )
	{
		results = results + "x";
	}
	else if ( input[i] == 'b' )
	{
		results = results + "y";
	}
	else if ( input[i] == 'a' )
	{
		results = results + "z";
	}
}
}
Last edited on
pearlyman (176)

The first thing I would consider is killing those {if else} statements, and go with something simpler like switch or arrays. There is an old saying... the more complicated the plumbing, the easier it is to stop up the pipes. 

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void decrypt( string input ) //"helper" decrypt function

switch results{
    case  'z' :
        results =+ "a";
        break;
        
    case 'y' :
        results =+"b";
         break;
         
    case 'x' : 
        results=+ "c";
	    break;
	    }
    default:
      cout << "Coder broken." << endl;


or...

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encoder[]={"z","y","x"};
decoder[]={"a","b","c"};


then use a loop 

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if (string==encoder[i]){
results=+decoder[i];
}


2nd, I'd ask myself if I really needed that header file.
Last edited on
hpardo11 (6)
Well this assignment uses automatic submission and grading and the header file is one thing it looks for so I can't really omit that.

I see how the large amount of if else statements isn't good practice but that was an example I saw so I just followed it and kept going.

So would changing the if else statements fix the blank output?
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