#include <iostream>
#include <fstream>
#include <string>
#include <vector>

using namespace std;

int main(int argc, char* argv[])
{
    ifstream infile;
    ofstream outfile;
    string feed, type, maxpx, comment;
    int cols, rows;
    const int SIZE = 3;

    infile.open("lena.pgm");
    getline(infile, type);
    infile >> rows >> cols;
    getline(infile, feed);
    getline(infile, maxpx);

    vector<vector<char>> image(rows, vector<char>(cols, '\0'));
    vector<vector<char>> out(rows, vector<char>(cols, '\0'));
    vector<vector<int>> filter = { { 0, -1, 0 }, { -1, 5, -1 }, { 0, -1, 0 } };

    for (int i = 0; i < rows; i++)
        for (int j = 0; j < cols; j++)
            infile >> image[i][j];
    infile.close();
    outfile.open("output.pgm");
    outfile << type << "\n" << comment << "\n" << rows << " " << cols << "\n" << maxpx << "\n";

    for (int i = SIZE / 2; i < rows - SIZE / 2; i++)
    {
        for (int j = SIZE / 2; j < cols - SIZE / 2; j++)
        {
            char sum = '\0';
            for (int k = -SIZE / 2; k <= SIZE / 2; k++)
            {
                for (int l = -SIZE / 2; l <= SIZE / 2; l++)
                {
                    sum += image[i+k][j+l] * filter[k + SIZE / 2][l + SIZE / 2];
                }
            }
            out[i][j] = sum;
        }
    }

    for (int i = 0; i < rows; i++)
        for (int j = 0; j < cols; j++)
            outfile << image[i][j];

    outfile.close();

    return 0;
}