ProblemProcessor.h

#pragma once
#include <iostream>
#include <string>
#include <memory>

class LineReader
{
private:
    std::istream& source;
public:
    LineReader(std::istream&);
    class LineProcessor
    {
    private:
        const char* buffer;
    protected:
        const std::string get_string();
        virtual const std::string process(const std::string) = 0;
    public:
        LineProcessor(const char*);
        virtual std::ostream& operator << ( std::ostream& ) = 0;
    }
    virtual const char* get_line()
    virtual std::auto_ptr<LineProcessor> next() = 0;
};