gistfile1.hh

#include <iostream>
using namespace std;

int btn[5][5];
int tbl[3][3];
void init();
void onoff(int, int);
int check(int, int);

int pow[25];

int main() {
	pow[1] = 2;
	pow[2] = 4;
	pow[3] = 8;
	pow[4] = 16;
	pow[5] = 32;
	pow[6] = 64;
	pow[7] = 128;
	pow[8] = 256;
	pow[9] = 512;
	pow[10] = 1024;
	pow[11] = 2048;
	pow[12] = 4096;
	pow[13] = 8192;
	pow[14] = 16384;
	pow[15] = 32768;
	pow[16] = 65536;
	pow[17] = 131072;
	pow[18] = 262144;
	pow[19] = 524288;
	pow[20] = 1048576;
	pow[21] = 2097152;
	pow[22] = 4194304;
	pow[23] = 8388608;
	pow[24] = 16777216;
	pow[25] = 33554432;
	int r, c, cases = 1;
	while (cin >> r >> c && r && c) {
		int b = 26;
		int ans = -1;
		char ch;
		for (int i = 0; i < 3; i++) {
			for (int j = 0; j < 3; j++) {
				cin >> ch;
				if (ch == '*') {
					tbl[i][j] = 1;
				} else {
					tbl[i][j] = 0;
				}
			}
		}
		for (int s = 0; s < pow[r * c]; s++) {
			init();
			int cnt = 1;
			int now = 0;
			int flag = 0;
			for (int i = 0; i < r; i++) {
				for (int j = 0; j < c; j++) {
					if (i >= 2) {
						for (int k = 0; k < c; k++) {
							if (btn[i - 2][k] == 0) {
								flag = 1;
								break;
							}
						}
					}
					if ((s % pow[cnt++]) >> (cnt - 1) == 1) {
						onoff(i, j);
						now++;
						if (now >= b) {
							flag = 1;
						}
					}
					if (flag == 1) {
						break;
					}
				}
				if (flag == 1) {
					break;
				}
			}
			if (flag == 1) {
				continue;
			}
			if (check(r, c)) {
				b = now;
				ans = s;
			}
		}
		cout << "Case #" << cases++ << endl;
		if (ans == -1) {
			cout << "Impossible." << endl;
		} else {
			int first = 0;
			for (int i = 1; i <= r * c; i++) {
				if ((ans % pow[i]) >> (i - 1) == 1) {
					if (first == 0) {
						cout << i;
						first = 1;
					} else {
						cout << " " << i;
					}
				}
			}
			cout << endl;
		}
		
	}
	return 0;
}

void init() {
	for (int i = 0; i < 5; i++) {
		for (int j = 0; j < 5; j++) {
			btn[i][j] = 0;
		}
	}
}

void onoff(int x, int y) {
	if (tbl[0][0] == 1 && x - 1 >= 0 && y - 1 >= 0) {
		btn[x - 1][y - 1] = !btn[x - 1][y - 1];
	}
	if (tbl[0][1] == 1 && x - 1 >= 0) {
		btn[x - 1][y] = !btn[x - 1][y];
	}
	if (tbl[0][2] == 1 && x - 1 >= 0 && y + 1 <= 4) {
		btn[x - 1][y + 1] = !btn[x - 1][y + 1];
	}
	if (tbl[1][0] == 1 && y - 1 >= 0) {
		btn[x][y - 1] = !btn[x][y - 1];
	}
	if (tbl[1][1] == 1) {
		btn[x][y] = !btn[x][y];
	}
	if (tbl[1][2] == 1 && y + 1 <= 4) {
		btn[x][y + 1] = !btn[x][y + 1];
	}
	if (tbl[2][0] == 1 && x + 1 <= 4 && y - 1 >= 0) {
		btn[x + 1][y - 1] = !btn[x + 1][y - 1];
	}
	if (tbl[2][1] == 1 && x + 1 <= 4) {
		btn[x + 1][y] = !btn[x + 1][y];
	}
	if (tbl[2][2] == 1 && x + 1 <= 4 && y + 1 <= 4) {
		btn[x + 1][y + 1] = !btn[x + 1][y + 1];
	}
}

int check(int r, int c) {
	for (int i = 0; i < r; i++) {
		for (int j = 0; j < c; j++) {
			if (btn[i][j] == 0) {
				return 0;
			}
		}
	}
	return 1;
}