import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    private static int WALL = -1;
    private static int DEATH = -2;
    private static int VISITED = -10;
    private static int EXIT = -100;
    private static int x;
    private static int y;
    private static int n;
    private static int m;
    private static int k;
    private static int deathMove = 0;
    private static int exitMove = 0;
    private static int[][] neib = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        n = in.nextInt();
        m = in.nextInt();
        k = in.nextInt();
        String[] maze = new String[n];
        for(int i = 0; i < n; i++){
            maze[i] = in.next();
        }
        int[][] data = convert(maze);
//        print(data);
        for(int a0 = 0; a0 < k; a0++){
            int i1 = in.nextInt();
            int j1 = in.nextInt();
            int i2 = in.nextInt();
            int j2 = in.nextInt();
            data[i1][j1] = tunel(i2, j2);
            data[i2][j2] = tunel(i1, j1);
            if (isDead(data, i1, j1)) {
                data[i2][j2] = DEATH;
            }
            if (isDead(data, i2, j2)) {
                data[i1][j1] = DEATH;
            }
//            if (isExit(data, i1, j1)) {
//                data[i2][j2] = EXIT;
//            }
//            if (isExit(data, i2, j2)) {
//                data[i1][j1] = EXIT;
//            }
        }
//        System.out.println();
//        print(data);
        calculate(data);
    }

    private static void print(int[][] data) {
        for (int[] r : data) {
            for (int i : r) {
                char c = '_';
                if (i == WALL) c = '#';
                else if (i == DEATH) c = '*';
                else if (i > 0) c = 'O';
                else if (i == EXIT) c = 'E';
                System.out.print(c);
            }
            System.out.println();
        }
    }

    private static boolean isDead(int[][] data, int x, int y) {
        for (int[] n : neib) if (data[x + n[0]][y + n[1]] != WALL) return false; // at least one is not wall
        return true;
    }

    private static void calculate(int[][] data) {
        boolean v[][] = new boolean[n + 2][m + 2];
        // DFS reachability starting with x, y
        move(v, data, x, y);
//        System.out.println("EXIT MOVES:" + exitMove);
//        System.out.println("DEATH MOVE:" + deathMove);
        double t = exitMove;
        double b = deathMove + exitMove;
        System.out.println(t / b);
    }

    private static void move(boolean[][] v, int[][] data, int x, int y) {
//        System.out.println("CHECK " + x + "," + y);
        if (data[x][y] == DEATH) {
//            System.out.println("DEATH");
            deathMove++;
        }
        else if (data[x][y] == EXIT) {
//            System.out.println("EXIT");
            exitMove++;
        }
        else {
//            System.out.println("PROCEED");
            v[x][y] = true;
            for (int[] n : neib) {
                if (!v[x + n[0]][y + n[1]] && data[x + n[0]][y + n[1]] != WALL) move(v, data, x + n[0], y + n[1]);
            }
        }
    }

    private static int tunel(int i, int j) {return i * m + j;}

    private static int[][] convert(String[] maze) {
        int[][] result = new int[n + 2][m + 2];
        for (int i = 0; i < n + 2; i++) {
            result[i][0] = WALL;
            result[i][m + 1] = WALL;
        }
        for (int i = 0; i < m + 2; i++) {
            result[0][i] = WALL;
            result[n + 1][i] = WALL;
        }

        for (int r = 0; r < n; r++) {
            for (int c = 0; c < m; c++) {
                char s = maze[r].charAt(c);
                if (s == '#') result[r + 1][c + 1] = WALL;
                else if (s == 'A') {
                    x = r + 1;
                    y = c + 1;
                } else if (s == '*') result[r + 1][c + 1] = DEATH;
                else if (s == '%') result[r + 1][c + 1] = EXIT;
            }
        }
        return result;
    }
}