import java.util.*;
import java.io.*;

public class tiling {

    private static class Domino {

        public Domino(int x, int y) {
            this.x = x;
            this.y = y;
        }
        int x, y;
    }

    private static class Position {

        public Position(int x, int y, int u, int o) {
            this.x = x;
            this.y = y;
            dx = u;
            dy = o;
        }
        int x, y;
        int dx, dy;
    }
    private static boolean first;
    private static int count;
    private static int map[][];
    private static char charMap[][];
    private static List<Domino> tiles;
    private static List<List<Position>> positions;

    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int width, height, num_tiles;
        StringTokenizer st;
        int a, b, k, origA, origB, stepsA, stepsB, meet;
        boolean done;
        while (true) {
            st = new StringTokenizer(br.readLine());
            height = Integer.parseInt(st.nextToken());
            width = Integer.parseInt(st.nextToken());
            num_tiles = Integer.parseInt(st.nextToken());
            if(height == 0 && width == 0 && num_tiles==0)
                break;
            tiles = new ArrayList<Domino>();
            st = new StringTokenizer(br.readLine());
            map = new int[height + 2][width + 2];
            charMap = new char[height + 2][width + 2];
            while (st.hasMoreTokens()) {
                tiles.add(new Domino(Integer.parseInt(st.nextToken()), Integer.parseInt(st.nextToken())));
            }
            int i, j;
            for (i = 1; i <= height; i++) {
                st = new StringTokenizer(br.readLine());
                for (j = 1; j <= width; j++) {
                    char c = st.nextToken().charAt(0);
                    if (c == 'X') {
                        charMap[i][j] = 'X';
                        map[i][j] = -1;
                    } else {
                        map[i][j] = Character.getNumericValue(c);
                    }
                }
                map[i][0] = -1;
                map[i][width + 1] = -1;
            }
            for (j = 0; j < width+2; j++) {
                map[0][j] = -1;
                map[height + 1][j] = -1;
            }
            
            positions = new ArrayList<List<Position>>();
            for (Domino d : tiles) {
                List<Position> possible_positions = new ArrayList<Position>();
                for (i = 1; i <= height; i++) {
                    for (j = 1; j <= width; j++) {
                        if (map[i][j] == d.x) {
                            if (map[i][j + 1] == d.y) {
                                possible_positions.add(new Position(i, j, 0, 1));
                            }
                            if (map[i][j - 1] == d.y && d.x != d.y) {
                                possible_positions.add(new Position(i, j, 0, -1));
                            }
                            if (map[i + 1][j] == d.y) {
                                possible_positions.add(new Position(i, j, 1, 0));
                            }
                            if (map[i - 1][j] == d.y && d.x != d.y) {
                                possible_positions.add(new Position(i, j, -1, 0));
                            }
                        }
                    }
                }
                positions.add(possible_positions);
            }

            first = true;
            count = 0;
            place_tile(0);
            if(count == 0){
                System.out.println("impossible");
            }else{
                System.out.println(count-1);
            }
            System.out.println();
            br.readLine();
        }

    }

    public static void place_tile(int i) {
        if (i == tiles.size()) {
            if (first) {
                for (int j = 1; j < map.length - 1; j++) {
                    for (int k = 1; k < map[0].length - 1; k++) {
                        System.out.print(charMap[j][k]);
                    }
                    System.out.println();
                }
            }
            first = false;
            count++;
            return;
        }
        for (Position p : positions.get(i)) {
            char x = charMap[p.x][p.y];
            char y = charMap[p.x + p.dx][p.y + p.dy];
            if (x == '[' || x == ']' || x == 'n' || x == 'u') {
                continue;
            }
            if (y == '[' || y == ']' || y == 'n' || y == 'u') {
                continue;
            }
            if (p.dx == 0) {
                if (p.dy == -1) {
                    charMap[p.x][p.y - 1] = '[';
                    charMap[p.x][p.y] = ']';
                } else {
                    charMap[p.x][p.y] = '[';
                    charMap[p.x][p.y + 1] = ']';
                }
            } else {
                if (p.dx == -1) {
                    charMap[p.x - 1][p.y] = 'n';
                    charMap[p.x][p.y] = 'u';
                } else {
                    charMap[p.x][p.y] = 'n';
                    charMap[p.x + 1][p.y] = 'u';
                }
            }
            place_tile(i + 1);
            charMap[p.x][p.y] = 'H';
            charMap[p.x + p.dx][p.y + p.dy] = 'H';
        }
    }
}