#include <iostream>
#include <fstream>

int main()
{
    constexpr size_t Columns = 4;
    constexpr size_t Rows = 4;
    constexpr size_t Samples = 3;

    constexpr unsigned char samples [Rows][Columns][Samples] = {
        { { 255, 0, 0 }, { 127, 63, 0 }, { 36, 127, 0 }, { 0, 255, 0 } },
        { { 255, 0, 0 }, { 127, 63, 0 }, { 36, 127, 0 }, { 0, 255, 0 } },
        { { 255, 0, 0 }, { 127, 63, 0 }, { 36, 127, 0 }, { 0, 255, 0 } },
        { { 255, 0, 0 }, { 127, 63, 0 }, { 36, 127, 0 }, { 0, 255, 0 } },
    };

    try
    {
        std::ofstream ofs;
        ofs.exceptions(std::ios::failbit);
        ofs.open("myfile.ppm");

        ofs << "P3\n" << Rows << ' ' << Columns << "\n255\n";

        for (size_t row = 0; row < Rows; ++row)
        {
            for (size_t column = 0; column < Columns; ++column)
            {
                for (size_t sample = 0; sample < Samples; ++sample)
                {
                    ofs << static_cast<unsigned>(samples[row][column][sample]) << '\n';
                }
            }
        }
    }
    catch(const std::ios_base::failure & failure)
    {
        std::cerr << failure.what();
        std::cin.get();
    }
}