import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class FileParser {

    public float[][] getMatrixFromFile(String filename) throws IOException {
        Stream<String> stream = Files.lines(Paths.get(filename));

        List<String> lines = stream.collect(Collectors.toList());

        int size = getMatrixSize(lines.get(0));
        float[][] matrix = new float[size][size+1];

        int row = 0;
        int col = 0;
        for (String line : lines.subList(1, lines.size() - 1)) {
            for (String s : line.split(" ")) {
                try {
                    matrix[row][col] = Float.parseFloat(s);
                    col += 1;
                } catch (NumberFormatException e) {}
            }
            row += 1;
            col = 0;
        }
        fillLastColumn(matrix, lines.get(lines.size() -1));
        return matrix;
    }

    private int getMatrixSize(String line) {
        return Integer.parseInt(line);
    }

    private void fillLastColumn(float[][] matrix, String line) {
        int row = 0;
        int col = matrix.length;
        for (String s : line.split(" ")) {
            matrix[row][col] = Float.parseFloat(s);
            row += 1;
        }
    }
}