Task: Move-to-front algorithm

C: #include<stdio.h>
#include<stdlib.h>
#include<string.h>

#define MAX_SIZE 100

int move_to_front(char *str,char c)
{
    char *q,*p;
    int shift=0;
    p=(char *)malloc(strlen(str)+1);
    strcpy(p,str);
    q=strchr(p,c); 
    shift=q-p;      
    strncpy(str+1,p,shift);
    str[0]=c;
    free(p);
  
    return shift;
}

void decode(int* pass,int size,char *sym)
{
    int i,index;
    char c;
    char table[]="abcdefghijklmnopqrstuvwxyz";
    for(i=0;i<size;i++)
    {
        c=table[pass[i]];
        index=move_to_front(table,c);
        if(pass[i]!=index) printf("there is an error");
        sym[i]=c;
    }
    sym[size]='\0';
}

void encode(char *sym,int size,int *pass)
{
    int i=0;
    char c;
    char table[]="abcdefghijklmnopqrstuvwxyz";
    for(i=0;i<size;i++)
    {
        c=sym[i];
        pass[i]=move_to_front(table,c);
    }
}

int check(char *sym,int size,int *pass)
{
    int *pass2=malloc(sizeof(int)*size);
    char *sym2=malloc(sizeof(char)*size);
    int i,val=1;

    encode(sym,size,pass2);
    i=0;
    while(i<size && pass[i]==pass2[i])i++;
    if(i!=size)val=0;

    decode(pass,size,sym2);
    if(strcmp(sym,sym2)!=0)val=0;

    free(sym2);
    free(pass2);

    return val;
}

int main()
{
    char sym[3][MAX_SIZE]={"broood","bananaaa","hiphophiphop"};
    int pass[MAX_SIZE]={0};
    int i,len,j;
    for(i=0;i<3;i++)
    {
        len=strlen(sym[i]);
        encode(sym[i],len,pass);
        printf("%s : [",sym[i]);
        for(j=0;j<len;j++)
            printf("%d ",pass[j]);
        printf("]\n");
        if(check(sym[i],len,pass))
            printf("Correct :)\n");
        else
            printf("Incorrect :(\n");
    }
    return 0;
}


C++: #include <iostream>
#include <iterator>
#include <sstream>
#include <vector>

using namespace std;

class MTF
{
public:
    string encode( string str )
    {
	fillSymbolTable();
	vector<int> output;
	for( string::iterator it = str.begin(); it != str.end(); it++ )
	{
	    for( int i = 0; i < 26; i++ )
	    {
		if( *it == symbolTable[i] )
		{
		    output.push_back( i );
		    moveToFront( i );
		    break;
		}
	    }
	}
	string r;
	for( vector<int>::iterator it = output.begin(); it != output.end(); it++ )
	{
	    ostringstream ss;
	    ss << *it;
	    r += ss.str() + " ";
	}
	return r;
    }

    string decode( string str )
    {
	fillSymbolTable();
	istringstream iss( str ); vector<int> output;
	copy( istream_iterator<int>( iss ), istream_iterator<int>(), back_inserter<vector<int> >( output ) );
	string r;
	for( vector<int>::iterator it = output.begin(); it != output.end(); it++ )
	{
	    r.append( 1, symbolTable[*it] );
	    moveToFront( *it );
	}
	return r;
    }

private:
    void moveToFront( int i )
    {
	char t = symbolTable[i];
	for( int z = i - 1; z >= 0; z-- )
	    symbolTable[z + 1] = symbolTable[z];

        symbolTable[0] = t;
    }

    void fillSymbolTable()
    {
        for( int x = 0; x < 26; x++ )
	    symbolTable[x] = x + 'a';
    }

    char symbolTable[26];
};

int main()
{
    MTF mtf;
    string a, str[] = { "broood", "bananaaa", "hiphophiphop" };
    for( int x = 0; x < 3; x++ )
    {
        a = str[x];
        cout << a << " -> encoded = ";
        a = mtf.encode( a );
        cout << a << "; decoded = " << mtf.decode( a ) << endl;
    }
    return 0;
}