read numbers from a file stream, split them to evens and odds then print to other two file streams. C++ Primer 5th 10.33

split_number.cpp

#include <fstream>

int main(int argc, char const *argv[])
{
    std::ifstream input(argv[1]);
    std::ofstream output_odd_number(argv[2]);
    std::ofstream output_even_number(argv[3]);

    std::istream_iterator<int> in_iter(input), eof;
    std::ostream_iterator<int> output_odd_number_iter(output_odd_number, " ");
    std::ostream_iterator<int> output_even_number_iter(output_even_number, " ");

    while (in_iter != eof)
        ((*in_iter % 2 == 0) ? output_even_number_iter : output_odd_number_iter) = *in_iter++;

    output_even_number << std::endl;
    output_odd_number << std::endl;

    output_odd_number.close();
    output_even_number.close();
    input.close();

    return 0;
}

for zsh user, if no line 16 and 17, cat output files will print a percent sign. Otherwise, export PROMPT_EOL_MARK="" to solve it.

more information: percent sign