#include <bits/stdc++.h>
#define int long long
#define VERTICAL 1
#define HORIZONTAL 2
#define NOT_DONE 1
#define DONE 2
using namespace std;
void open(){
if(fopen("input.inp", "r")){
freopen("input.inp", "r", stdin);
//freopen("output.out", "w", stdout);
}
}
const int maxn = 1e7;
int n, m;
char board[3001][3001];
vector<int> G[maxn];
int vertical_change[3001][3001], horizontal_change[3001][3001];
pair<int, int> vertical_parent[3001][3001], horizontal_parent[3001][3001];
bool vertical_check[3001][3001], horizontal_check[3001][3001];
int cnt;
int state[3001][3001];
bool check[maxn];
int bfs(int root){
queue<pair<int, bool>> q;
q.push({root, true});
int total = 0;
int cur = 0;
while(!q.empty()){
pair<int, int> first = q.front();
q.pop();
int u = first.first;
if(check[u]) continue;
check[u] = true;
total++;
cur += first.second;
for(int v : G[u]){
q.push({v, first.second ^ 1});
}
}
return max(cur, total - cur);
}
void build(int x, int y, int direction){
if(state[x][y]) return;
state[x][y] = NOT_DONE;
if(direction == VERTICAL){
int cur_index = vertical_change[x][y];
int new_index;
if(x + 3 > n || board[x + 1][y] != 'G' || board[x + 2][y] != 'W') return;
// To G:
if(horizontal_parent[x + 1][y] != make_pair(0ll, 0ll)){
pair<int, int> temp = horizontal_parent[x + 1][y];
new_index = horizontal_change[temp.first][temp.second];
if(state[temp.first][temp.second] != NOT_DONE){
G[cur_index].push_back(new_index);
G[new_index].push_back(cur_index);
build(temp.first, temp.second, HORIZONTAL);
}
}
// To W:
if(horizontal_parent[x + 2][y] != make_pair(0ll, 0ll)){
pair<int, int> temp = horizontal_parent[x + 2][y];
new_index = horizontal_change[temp.first][temp.second];
if(state[temp.first][temp.second] != NOT_DONE){
G[cur_index].push_back(new_index);
G[new_index].push_back(cur_index);
build(temp.first, temp.second, HORIZONTAL);
}
}
}else{
int cur_index = horizontal_change[x][y];
int new_index;
if(y + 3 > m || board[x][y + 1] != 'G' || board[x][y + 2] != 'W') return;
// To G:
if(vertical_parent[x][y + 1] != make_pair(0ll, 0ll)){
pair<int, int> temp = vertical_parent[x][y + 1];
new_index = vertical_change[temp.first][temp.second];
if(state[temp.first][temp.second] != NOT_DONE){
G[cur_index].push_back(new_index);
G[new_index].push_back(cur_index);
build(temp.first, temp.second, VERTICAL);
}
}
// To W:
if(vertical_parent[x][y + 1] != make_pair(0ll, 0ll)){
pair<int, int> temp = vertical_parent[x][y + 1];
new_index = vertical_change[temp.first][temp.second];
if(state[temp.first][temp.second] != NOT_DONE){
G[cur_index].push_back(new_index);
G[new_index].push_back(cur_index);
build(temp.first, temp.second, VERTICAL);
}
}
}
state[x][y] = DONE;
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
open();
cin >> n >> m;
for(int i = 1; i <= n; i++){
for(int j = 1; j <= m; j++){
cin >> board[i][j];
}
}
cnt = 0;
for(int i = 1; i <= n; i++){
for(int j = 1; j <= m; j++){
if(board[i][j] == 'R'){
vertical_parent[i][j] = make_pair(i, j);
horizontal_parent[i][j] = make_pair(i, j);
// horizontal:
if(j + 2 <= m && board[i][j + 1] == 'G' && board[i][j + 2] == 'W'){
horizontal_change[i][j] = ++cnt;
horizontal_parent[i][j + 1] = horizontal_parent[i][j + 2] = horizontal_parent[i][j];
horizontal_check[i][j] = true;
}
// vertical:
if(i + 2 <= n && board[i + 1][j] == 'G' && board[i + 2][j] == 'W'){
vertical_change[i][j] = ++cnt;
vertical_parent[i + 1][j] = vertical_parent[i + 2][j] = vertical_parent[i][j];
vertical_check[i][j] = true;
}
}
}
}
if(cnt == 0){
cout << 0 << endl;
return 0;
}
for(int i = 1; i <= n; i++){
for(int j = 1; j <= n; j++){
if(board[i][j] == 'R'){
build(i, j, VERTICAL);
build(i, j, HORIZONTAL);
if(vertical_check[i][j] && horizontal_check[i][j]){
G[vertical_change[i][j]].push_back(horizontal_change[i][j]);
G[horizontal_change[i][j]].push_back(vertical_change[i][j]);
}
}
}
}
int result = 0;
for(int i = 1; i <= cnt; i++){
if(!check[i]){
result += bfs(i);
}
}
cout << result << endl;
return 0;
}
Compilation message
dango_maker.cpp: In function 'void open()':
dango_maker.cpp:12:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
12 | freopen("input.inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
99 ms |
235084 KB |
Output is correct |
| 2 |
Correct |
103 ms |
235148 KB |
Output is correct |
| 3 |
Correct |
104 ms |
235180 KB |
Output is correct |
| 4 |
Correct |
103 ms |
235084 KB |
Output is correct |
| 5 |
Correct |
116 ms |
235200 KB |
Output is correct |
| 6 |
Incorrect |
107 ms |
235176 KB |
Output isn't correct |
| 7 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
99 ms |
235084 KB |
Output is correct |
| 2 |
Correct |
103 ms |
235148 KB |
Output is correct |
| 3 |
Correct |
104 ms |
235180 KB |
Output is correct |
| 4 |
Correct |
103 ms |
235084 KB |
Output is correct |
| 5 |
Correct |
116 ms |
235200 KB |
Output is correct |
| 6 |
Incorrect |
107 ms |
235176 KB |
Output isn't correct |
| 7 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
99 ms |
235084 KB |
Output is correct |
| 2 |
Correct |
103 ms |
235148 KB |
Output is correct |
| 3 |
Correct |
104 ms |
235180 KB |
Output is correct |
| 4 |
Correct |
103 ms |
235084 KB |
Output is correct |
| 5 |
Correct |
116 ms |
235200 KB |
Output is correct |
| 6 |
Incorrect |
107 ms |
235176 KB |
Output isn't correct |
| 7 |
Halted |
0 ms |
0 KB |
- |
