[백준] P2583

import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class P2583 {

	/*
	 * 02 44 -> 01 32 , 11 25 -> 10 13 , 40 62 -> 43 54 => x, m-y2 x2-1 m-y1-1
	 */

	private static boolean[][] visit;
	private static int[] dx = { 0, 0, -1, 1 };
	private static int[] dy = { 1, -1, 0, 0 };
	private static int m, n;

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		m = sc.nextInt();
		n = sc.nextInt();
		int k = sc.nextInt(), rec[][] = new int[k][4], matrix[][] = new int[n][m];

		for (int i = 0; i < k; i++) {
			for (int j = 0; j < 4; j++) {
				rec[i][j] = sc.nextInt();
			}
		}
		for (int[] r : rec) {
			for (int i = 0; i < n; i++) {
				for (int j = 0; j < m; j++) {
					if ((r[0] <= i && r[2] - 1 >= i) && (m - r[3] <= j && m - r[1] - 1 >= j)) {
						matrix[i][j] = -1;
					}
				}
			}
		}
		solution(matrix);
		sc.close();
	}

	private static void solution(int[][] matrix) {
		int area = 0;
		ArrayList<Integer> list = new ArrayList<>();
		visit = new boolean[n][m];
		for (int i = 0; i < n; i++) {
			for (int j = 0; j < m; j++) {
				if (!visit[i][j] && matrix[i][j] != -1) {
					area++;
					list.add(dfs(matrix, i, j, matrix[i][j]));
				}
			}
		}
		System.out.println(area);
		Collections.sort(list);
		for (int ele : list) {
			System.out.print(ele + " ");
		}
	}

	private static int dfs(int[][] matrix, int x, int y, int current) {
		int cnt = 1;
		if (visit[x][y])
			return 0;
		for (int i = 0; i < 4; i++) {
			int newX = x + dx[i];
			int newY = y + dy[i];
			if (isValid(newX, newY) && current == matrix[newX][newY]) {
				visit[x][y] = true;
				cnt += dfs(matrix, newX, newY, matrix[newX][newY]);
			}
		}
		return cnt;
	}

	private static boolean isValid(int x, int y) {
		return x < 0 || x >= n || y < 0 || y >= m ? false : true;
	}
}