#include <cctype>
#include <string>

#include <cstring>
#include <vector>
#include <iostream>
#include <cstdio>
#include <cstdlib>

//Erase the first occurence of the character in the given string

std::string erase( const char *s, char c )
{
   std::string erased;
   

   for( ; *s && *s != c; ++s )
      erased.push_back( *s );
   
   for( (*s ? ++s: s); *s; ++s )
      erased.push_back( *s );

   
   return erased;
      
}


//Erase the first occurrence of s2 in s
std::string erase( const char *s, const char *s2 )

{
   std::string erased;
   const char *skip = NULL;
   int s2Len = strlen(s2);

   
   if( (skip = strstr( s, s2 )) )
   {
      for( ;s != skip; ++s )
         erased.push_back( *s );
         

      s += s2Len;
   }
   
   for( ; *s; ++s )
      erased.push_back( *s );
      

   return erased;
}


//Replace the first occurrence of olds with news in s
std::string replace( const char *s, const char *olds, const char *news )

{
   std::string replaced;
   const char *skip = NULL;
   const char *newsi = NULL;

   int oldsLen = strlen(olds);
   
   if( (skip = strstr( s, olds )) )
   {
      for( ;s != skip; ++s )

         replaced.push_back( *s );
         
      for( newsi = news; *newsi; ++newsi )
         replaced.push_back( *newsi );
               
      s += oldsLen;

   }
   for( ; *s; ++s )
      replaced.push_back( *s );
      
   return replaced;

}


//Erase all occurrences of the character in the given string
std::string eraseAll( const char *s, char c )
{

   std::string erased;
   
   for( ; *s; ++s )
      if( *s != c )
         erased.push_back( *s );
   

   return erased;
      
}


//Erase all occurrences of s2 in s
std::string eraseAll( const char *s, const char *s2 )

{
   std::string erased;
   const char *skip = NULL;
   int s2Len = strlen(s2);

   
   while( *s )
   {
      if( (skip = strstr( s, s2 )) )
      {
         for( ;s != skip; ++s )

            erased.push_back( *s );
         
         s += s2Len;
      }
      else
      {

         for( ; *s; ++s )
            erased.push_back( *s );
      }
   }
      
   return erased;

}


//Replace all occurrencs of olds with news in s
std::string replaceAll( const char *s, const char *olds, const char *news )

{
   std::string replaced;
   const char *skip = NULL;
   const char *newsi = NULL;

   int oldsLen = strlen(olds);
   
   while( *s )
   {
      if( (skip = strstr( s, olds )) )

      {
         for( ;s != skip; ++s )
            replaced.push_back( *s );
         
         for( newsi = news; *newsi; ++newsi )
            replaced.push_back( *newsi );

         
         s += oldsLen;
      }
      else
      {
         for( ; *s; ++s )

            replaced.push_back( *s );
      }
   }
      
   return replaced;
}