#include <stdio.h>
#include <stdlib.h>
#include <string.h>

double dohvati_max(double num1, double num2, double num3, double num4) {
    double max = num1;
    if (num2 > max) max = num2;
    if (num3 > max) max = num3;
    if (num4 > max) max = num4;
    return max;
}

double** max_pool_2d(double** mat, int N, int M) {
    double** rezMat = (double**) calloc(N/2, sizeof(double*));
    for (int i = 0, indexI = 0; i < N; i += 2, indexI++) {
        rezMat[indexI] = (double*) calloc(M/2, sizeof(double));
        for (int j = 0, indexJ = 0; j < M; j += 2, indexJ++) {
            rezMat[indexI][indexJ] = dohvati_max(mat[i][j], mat[i][j + 1], mat[i + 1][j], mat[i + 1][j + 1]);
        }
    }

    return rezMat;
}

int main() {
    int N;
    int M;
    scanf("%d %d", &N, &M);
    if(N % 2 != 0 || M % 2 != 0) {
        printf("Dimenzije ulazne matrice moraju biti parne.");
        return 0;
    }

    double** mat = (double**) calloc(N, sizeof(double*));
    for (int i = 0; i < N; i++) {
        mat[i] = (double*) calloc(M, sizeof(double));
        for (int j = 0; j < M; j++) {
            scanf("%lf", &mat[i][j]);
        }
    }

    FILE* fout = fopen("pool.txt", "w");
    double** rezMat = max_pool_2d(mat, N, M);
    for (int i = 0; i < N/2; i++) {
        for (int j = 0; j < M/2; j++) {
            fprintf(fout, "%.3f ", rezMat[i][j]);
        }
        fprintf(fout, "\n");
    }

    return 0;
}