#include<bits/stdc++.h>
using namespace std;
using ll = long long;
int n,m;
bool check(int i,int j){
return (i>=0 && j>=0 && i<n && j<m);
}
void solve(){
cin>>n>>m;
vector<string>v(n);
for(int i = 0;i<n;i++){
cin>>v[i];
}
vector<vector<int>>pref(n,vector<int>(m));
vector<vector<int>>e(n);
for(int i = 0;i<n;i++){
if(v[i][0]=='#'){
pref[i][0]=1;
e[i].push_back(0);
}
}
for(int i =0;i<n;i++){
for(int j = 1;j<m;j++){
pref[i][j]=pref[i][j-1]+(v[i][j]=='#');
if(v[i][j]=='#') e[i].push_back(j);
}
}
// for(int i =0;i<n;i++){
// for(int j = 0;j<m;j++){
// cout<<v[i][j];
// }
// cout<<endl;
// }
// return;
vector<vector<bool>>a,b,c,d;
a = b = c = d = vector<vector<bool>>(n,vector<bool>(m));
for(int i = 0;i<n;i++){
for(int j = 0;j<m;j++){
if(check(i+1,j-1) && check(i+1,j+1) && v[i][j]=='#' && v[i+1][j-1] == '#' && v[i+1][j+1] == '#' && v[i+1][j]=='.'){
// cout<<-1<<endl;
a[i][j] = 1;
b[i][j] = 1;
a[i + 1][j - 1] = 1;
b[i + 1][j + 1] = 1;
}
if(check(i-1,j-1) && check(i-1,j+1) && v[i][j]=='#' && v[i-1][j-1] == '#' && v[i-1][j+1] == '#' && v[i-1][j]=='.'){
c[i][j]=1;
d[i][j]=1;
c[i-1][j-1]=1;
d[i-1][j+1]=1;
}
}
}
for(int i = 0;i<n;i++){
for(int j = 0;j+1<e[i].size();j++){
int x1 = e[i][j];
int x2 = e[i][j+1];
if(pref[i][x2]-pref[i][x1]==1){
if(check(i-1,x1+1) && check(i-1,x2-1) && a[i-1][x1+1] && b[i-1][x2-1]){
a[i][x1]=1;
b[i][x2]=1;
}
}
}
}
for(int i = n-1;i>=0;i--){
for(int j = 0;j+1<e[i].size();j++){
int x1 = e[i][j];
int x2 = e[i][j+1];
if(pref[i][x2]-pref[i][x1]==1){
if(check(i+1,x1+1) && check(i+1,x2-1) && c[i+1][x1+1] && d[i+1][x2-1]){
c[i][x1]=1;
d[i][x2]=1;
}
}
}
}
int ans = 0;
for(int i = 1;i+1<n;i++){
for(int j = 0;j<e[i].size();j++){
int x1 = e[i][j];
int x2 = e[i][j+1];
if(a[i][x1] && c[i][x1] && b[i][x2] && d[i][x2]){
// cout<<i<<" "<<x1<<" "<<x2<<endl;
ans++;
}
}
}
cout<<ans<<endl;
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(nullptr);
solve();
}
Compilation message
Main.cpp: In function 'void solve()':
Main.cpp:58:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
58 | for(int j = 0;j+1<e[i].size();j++){
| ~~~^~~~~~~~~~~~
Main.cpp:70:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
70 | for(int j = 0;j+1<e[i].size();j++){
| ~~~^~~~~~~~~~~~
Main.cpp:83:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
83 | for(int j = 0;j<e[i].size();j++){
| ~^~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
340 KB |
Output is correct |
| 2 |
Correct |
1 ms |
452 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
340 KB |
Output is correct |
| 2 |
Correct |
1 ms |
452 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
