replace letters with strings

[4i67ko23]

Hi, I want to replace a character (Example 'A') with a string (Example 'abc123')
Is this possible?
I've this code: But your= can only replace one character with another.
replace( ENCODE_TEXT.begin(), ENCODE_TEXT.end(), '1', 'Q' );

[soranz]

U can only do that sort of thing with dynamically allocated containers like vectors which can change size as u need using push_back and erase methods.

http://www.cplusplus.com/reference/stl/vector/push_back/

[vlad from moscow]

Read you previous thread. There are some some examples of how to do this. I copied my example here.

std::string encode( const std::string &s )
{
	const char *from = "eo";   // substitute for your string literal
	const char *to[] = { "123", "456" };   // substitute for your string literals

	std::string t = s;
	
	for ( std::string::size_type pos = 0; pos < t.size(); /* */ )
	{
		pos = t.find_first_of( from, pos );
		if ( pos != std::string::npos )
		{
			std::string::size_type i = std::strchr( from, t[pos] ) - from;
			t.replace( pos, 1, to[i] );
			pos += std::strlen( to[i] );
		}
	}

	return ( t );
}

[4i67ko23]

thanks! Now, how can I make an encode function?
I tried to switch *from and *to, but that didn't work...

[vlad from moscow]

I have not understood your question. I showed you encode function. What is the problem?

[4i67ko23]

sorry, I mean 'decode'

[vlad from moscow]

Do you need a reverse operation?

[4i67ko23]

yes, like that, how does it work?

[vlad from moscow]

It can do not work due to a possible ambiguity of an interpretation of codes. First of all show your codes for encode.

[4i67ko23]

Well, this is my code now:

//--------------------------------------
#include <windows.h>
#include <algorithm>
#include <iostream>
#include <fstream>
#include <string>
//--------------------------------------
using namespace std;
//--------------------------------------
std::string encode( const std::string &s )
{
    const char *from = " 0123456789";   // substitute for your string literal
	const char *to[] = { "SPACE", "ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"};   // substitute for your string literals

	std::string t = s;
	
	for ( std::string::size_type pos = 0; pos < t.size(); /* */ )
	{
		pos = t.find_first_of( from, pos );
		if ( pos != std::string::npos )
		{
			std::string::size_type i = std::strchr( from, t[pos] ) - from;
			t.replace( pos, 1, to[i] );
			pos += std::strlen( to[i] );
		}
	}

	return ( t );
}
//--------------------------------------
std::string decode( const std::string &s )
{

    const char *from = { "SPACE", "ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"};   // substitute for your string literals
	const char *to[] = " 0123456789";   // substitute for your string literals

	std::string t = s;
	
	for ( std::string::size_type pos = 0; pos < t.size(); /* */ )
	{
		pos = t.find_first_of( from[], pos );
		if ( pos != std::string::npos )
		{
			std::string::size_type i = std::strchr( from[], t[pos] ) - from;
			t.replace( pos, 1, to[i] );
			pos += std::strlen( to[i] );
		}
	}

	return ( t );
}
//--------------------------------------
int main()
{
    string text_encode;
    text_encode = encode(" -0-1-2-3-4-5-6-7-8-9");
    cout << text_encode << endl;
    string text_decode;
    text_decode = decode(text_encode);
    cout << text_decode << endl;
    cin.get();
}

It's just to encode it and decode it back,,
Butt I get tons of errors

[vlad from moscow]

It is naturally that you get tons of errors because decode is writtten incorrectly.
You may not for example simply to write

    const char *from = { "SPACE", "ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"};   // substitute for your string literals
	const char *to[] = " 0123456789";   // substitute for your string literals 

by analogy with my code

    const char *from = " 0123456789";   // substitute for your string literal
	const char *to[] = { "SPACE", "ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"};   // substitute for your string literals 

because types of objects in your declarations are incorrect.

Function decode can not be writtten by means of simple copying of my function encode.

[4i67ko23]

Well, how can I do it? Because otherwise the encode function is useless..

[vlad from moscow]

It is much more difficult task. I think you need a special structure as for example a tree that to perform searching of words in an encoded string.

[tntxtnt]

if it is simply "find and replace" then I hope my code can help...

#include <iostream>
#include <string>
using namespace std;

//--------------------------------------
void replaceAll(string& s, const string& a, const string& b)
{
    //replace all a with b in s
    size_t pos = s.find(a);
    while (pos != string::npos)
    {
        s.replace(pos, a.length(), b);
        pos += b.length();
        pos = s.find(a, pos);
    }
}
//--------------------------------------
string cipher(const string& s, const string& command)
{
    const string from   = " 0123456789";
    const string to[11] = {"SPACE","ZERO","ONE","TWO","THREE","FOUR",
                           "FIVE","SIX","SEVEN","EIGHT","NINE"};
    string ret = s;

    if (command == "encode")
        for (int i = 0; i < from.length(); i++)
            replaceAll(ret, from.substr(i,1), to[i]);
    else if (command == "decode")
        for (int i = 0; i < from.length(); i++)
            replaceAll(ret, to[i], from.substr(i,1));
    
    return ret;
}
//--------------------------------------
int main()
{
    string textEncode;
    textEncode = cipher(" -0-1-2-3-4-5-6-7-8-9", "encode");
    cout << textEncode << endl;
    string textDecode;
    textDecode = cipher(textEncode, "decode");
    cout << textDecode << endl;
    cin.get();
    return 0;
}