#include <sstream>
#include <string>
#include <iostream>

using namespace std;

char readUntilCharInLine(istream& is, char untilChar, string& result)
{
    typedef istream::traits_type Traits;
    Traits::int_type i;

    while(is && (i = is.get()) != Traits::eof())
    {
        char c = Traits::to_char_type(i);
        if(c == untilChar || c == '\n')
            return c;
        result += c;
    }

    return 0;   
}

string convert(string input)
{
    istringstream is(input);
    string result;

    while(is)
    {
        readUntilCharInLine(is, ',', result);
        result += ';';

        readUntilCharInLine(is, ',', result);
        result += ';';

        readUntilCharInLine(is, '.', result);
        result += ',';

        readUntilCharInLine(is, ',', result);
        result += ';';

        readUntilCharInLine(is, '.', result);
        result += ',';

        readUntilCharInLine(is, '\n', result);
        result += '\n';
    }

    return result;
}

int main()
{
    std::cout << convert("27.09.2012,15:30:17,12.562,3.231\n"
"27.09.2012,15:30:17,12.125,3.144\n"
"27.09.2012,15:30:17,12.767,3.145\n"
"27.09.2012,15:30:18,12.660,3.260");
}