#include <iostream>
#include <sstream>
#include <iomanip>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <iterator>
#include <functional>
#include <complex>
#include <queue>
#include <stack>
#include <cmath>
#include <cassert>
#include <tuple>
using namespace std;
typedef long long LL;
typedef complex<double> CMP;
class Balance { public:
string canTransform(vector <string> initial, vector <string> target)
{
auto ti = gen_tree(initial);
auto tt = gen_tree(target);
return tree_eq(ti, tt) ? "Possible" : "Impossible";
}
vector<vector<int>> gen_tree(vector<string> s) {
s.push_back(string(s[0].size(), '#'));
s.insert(s.begin(), string(s[0].size(), '#'));
for(auto& si: s)
si = '#'+si+'#';
const int H = s.size(), W = s[0].size();
const int NOTYET = 0x7fffffff;
vector<vector<int>> tree;
vector<vector<int>> parent_cand(H, vector<int>(W, -1));
vector<vector<int>> color(H, vector<int>(W, NOTYET));
for(int y=0; y<H; ++y)
for(int x=0; x<W; ++x)
if(color[y][x]==NOTYET) {
const char ME = s[y][x];
int newId = tree.size();
tree.resize(newId+1);
// BFS
set<int> tonari;
queue<pair<int,int>> Q;
color[y][x] = newId;
Q.emplace(y, x);
while(!Q.empty()) {
int yy = Q.front().first;
int xx = Q.front().second;
Q.pop();
int dx[] = {-1,+1,0,0};
int dy[] = {0,0,-1,+1};
for(int d=0; d<4; ++d) {
int y2 = yy+dy[d];
int x2 = xx+dx[d];
if(0<=x2&&x2<W&&0<=y2&&y2<H) {
if(s[y2][x2]==ME&&color[y2][x2]==NOTYET) {
color[y2][x2] = newId;
Q.emplace(y2, x2);
}
if(s[y2][x2]!=ME&&color[y2][x2]!=NOTYET) {
tonari.insert(color[y2][x2]);
}
}
}
}
if(tonari.size() == 1)
tree[*tonari.begin()].push_back(newId);
}
return tree;
}
map<vector<int>, int> hashId;
bool tree_eq(const vector<vector<int>>& a, const vector<vector<int>>& b)
{
return hash(a,0) == hash(b,0);
}
int hash(const vector<vector<int>>& a, int r)
{
vector<int> ch;
for(int v: a[r])
ch.push_back(hash(a, v));
sort(ch.begin(), ch.end());
if(hashId.count(ch))
return hashId[ch];
int v = hashId.size();
return hashId[ch] = v;
}
};
// BEGIN CUT HERE
#include <ctime>
double start_time; string timer()
{ ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
{ os << "{ ";
for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
void verify_case(const string& Expected, const string& Received) {
bool ok = (Expected == Received);
if(ok) cerr << "PASSED" << timer() << endl; else { cerr << "FAILED" << timer() << endl;
cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
#define END verify_case(_, Balance().canTransform(initial, target));}
int main(){
CASE(0)
string initial_[] = {"#"};
vector <string> initial(initial_, initial_+sizeof(initial_)/sizeof(*initial_));
string target_[] = {"."};
vector <string> target(target_, target_+sizeof(target_)/sizeof(*target_));
string _ = "Impossible";
END
CASE(1)
string initial_[] = {"..",
".."};
vector <string> initial(initial_, initial_+sizeof(initial_)/sizeof(*initial_));
string target_[] = {".#",
"##"};
vector <string> target(target_, target_+sizeof(target_)/sizeof(*target_));
string _ = "Possible";
END
CASE(2)
string initial_[] = {"...",
".#.",
"..."};
vector <string> initial(initial_, initial_+sizeof(initial_)/sizeof(*initial_));
string target_[] = {"###",
"#.#",
"###"};
vector <string> target(target_, target_+sizeof(target_)/sizeof(*target_));
string _ = "Impossible";
END
CASE(3)
string initial_[] = {".#.#.......",
"####.###...",
".....####..",
"..##.#.##.#",
".##..#.##.#",
".#######...",
".#....###.#",
".##.#.#....",
"..#...#...#",
"..#####...#",
"..........."};
vector <string> initial(initial_, initial_+sizeof(initial_)/sizeof(*initial_));
string target_[] = {"...........",
".###....#..",
".#.#..#....",
".###.......",
".#####.....",
".#...#####.",
".#.#.....#.",
".#.#####.#.",
".#.......#.",
".#########.",
"..........."};
vector <string> target(target_, target_+sizeof(target_)/sizeof(*target_));
string _ = "Impossible";
END
CASE(4)
string initial_[] = {".....",
".###.",
".....",
".###.",
"....."};
vector <string> initial(initial_, initial_+sizeof(initial_)/sizeof(*initial_));
string target_[] = {".....",
".#.#.",
".#.#.",
".#.#.",
"....."};
vector <string> target(target_, target_+sizeof(target_)/sizeof(*target_));
string _ = "Possible";
END
/*
CASE(5)
string initial_[] = ;
vector <string> initial(initial_, initial_+sizeof(initial_)/sizeof(*initial_));
string target_[] = ;
vector <string> target(target_, target_+sizeof(target_)/sizeof(*target_));
string _ = ;
END
CASE(6)
string initial_[] = ;
vector <string> initial(initial_, initial_+sizeof(initial_)/sizeof(*initial_));
string target_[] = ;
vector <string> target(target_, target_+sizeof(target_)/sizeof(*target_));
string _ = ;
END
*/
}
// END CUT HERE