#include "rect.h"
#include<bits/stdc++.h>
using namespace std;
using ll = int;
using lll = long long;
const ll maxn = 2500;
struct dsu{
vector<ll> p;
dsu(ll N):p(N,-1){}
ll g(ll i){
return p[i]<0?i:p[i] = g(p[i]);
}
bool m(ll a,ll b){
a = g(a),b = g(b);
if (a==b) return false;
if (p[a]>p[b]) swap(a,b);
p[a] += p[b];
p[b] = a;
return true;
}
};
long long count_rectangles(std::vector<std::vector<int> > a) {
ll n = a.size(), m = a[0].size();
if (n<3||m<3) return 0;
ll sub6 = 1;
for(auto &o : a) for(ll &i : o) if (i>1) sub6 = 0;
if (sub6){
dsu d(n*m);
for(ll i = 1;i<n-1;i++){
for(ll j = 1;j<m-1;j++){
if(i>1&&!a[i][j]&&!a[i-1][j]){
d.m((i)*m+(j),(i-1)*m+(j));
}
if(j>1&&!a[i][j]&&!a[i][j-1]){
d.m((i)*m+(j),(i)*m+(j-1));
}
}
}
vector<ll> gs;
for(ll i = 1;i<n-1;i++){
for(ll j = 1;j<m-1;j++){
if(!a[i][j]){
gs.push_back(d.g((i)*m+(j)));
}
}
}
sort(gs.begin(),gs.end());
gs.erase(unique(gs.begin(),gs.end()),gs.end());
ll gc = gs.size();
vector<vector<pair<ll,ll>>> ps(gc);
for(ll i = 1;i<n-1;i++){
for(ll j = 1;j<m-1;j++){
if(!a[i][j]){
ll p = d.g((i)*m+(j));
ll idx = lower_bound(gs.begin(),gs.end(),p)-gs.begin();
ps[idx].push_back({i,j});
}
}
}
ll ans = 0;
for(auto &o : ps){
ll x1 = o[0].first, x2=o[0].first, y1=o[0].second, y2=o[0].second;
for(auto [x,y] : o){
x1 = min(x,x1);
x2 = max(x,x2);
y1 = min(y,y1);
y2 = max(y,y2);
}
ll req = (x2-x1+1)*(y2-y1+1);
if (req==o.size()) ans++;
}
return ans;
}
vector<vector<pair<ll,ll>>> row(n),col(m);
for(ll i = 0;i<n;i++){
vector<pair<ll,ll>> st;
for(ll j = 0;j<m;j++){
while(st.size()&&st.back().first<a[i][j]){
if(j>st.back().second+1)row[i].push_back({st.back().second,j});
st.pop_back();
}
if(st.size()){
if(j>st.back().second+1)row[i].push_back({st.back().second,j});
}
if (st.size()&&st.back().first==a[i][j]) st.pop_back();
st.push_back({a[i][j],j});
}
}
for(ll j = 0;j<m;j++){
vector<pair<ll,ll>> st;
for(ll i = 0;i<n;i++){
while(st.size()&&st.back().first<a[i][j]){
if(i>st.back().second+1)col[j].push_back({st.back().second,i});
st.pop_back();
}
if(st.size()){
if(i>st.back().second+1)col[j].push_back({st.back().second,i});
}
if (st.size()&&st.back().first==a[i][j]) st.pop_back();
st.push_back({a[i][j],i});
}
}
for(auto &o : row) sort(o.begin(),o.end());
for(auto &o : col) sort(o.begin(),o.end());
vector<vector<ll>> down(n,vector<ll>(m,0)),up(n,vector<ll>(m,n));
for(ll i = 0;i<m;i++){
for(auto [l,r] : col[i]){
down[l][i] = r;
up[l][i] = min(up[l][i],r);
}
}
lll ans = 0;
for(ll r1 = 1;r1<n-1;r1++){
vector<pair<ll,ll>> cur = row[r1];
vector<pair<ll,ll>> nw;
for(ll r2 = r1;r2<n-1;r2++){
if(r2>r1){
for(auto &o : cur){
if (binary_search(row[r2].begin(),row[r2].end(),o)){
nw.push_back(o);
}
}
nw.swap(cur);
nw.clear();
}
pair<ll,ll> t = {r1-1,r2+1};
vector<ll> ok(m,0);
for(ll i = 0;i<m;i++) ok[i] = down[r1-1][i]>r2&&up[r1-1][i]-1<=r2&&binary_search(col[i].begin(),col[i].end(),t);
vector<ll> p(m+1,0);
for(ll i = 0;i<m;i++) p[i+1] = p[i]+ok[i];
for(auto &o : cur){
if (p[o.second]-p[o.first+1]==(o.second-o.first-1)) ans++;
}
}
}
return ans;
}
Compilation message
rect.cpp: In function 'long long int count_rectangles(std::vector<std::vector<int> >)':
rect.cpp:71:11: warning: comparison of integer expressions of different signedness: 'll' {aka 'int'} and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
71 | if (req==o.size()) ans++;
| ~~~^~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
344 KB |
Output is correct |
| 2 |
Correct |
1 ms |
344 KB |
Output is correct |
| 3 |
Correct |
0 ms |
348 KB |
Output is correct |
| 4 |
Correct |
1 ms |
344 KB |
Output is correct |
| 5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 6 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
344 KB |
Output is correct |
| 2 |
Correct |
1 ms |
344 KB |
Output is correct |
| 3 |
Correct |
0 ms |
348 KB |
Output is correct |
| 4 |
Correct |
1 ms |
344 KB |
Output is correct |
| 5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 6 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
344 KB |
Output is correct |
| 2 |
Correct |
1 ms |
344 KB |
Output is correct |
| 3 |
Correct |
0 ms |
348 KB |
Output is correct |
| 4 |
Correct |
1 ms |
344 KB |
Output is correct |
| 5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 6 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
344 KB |
Output is correct |
| 2 |
Correct |
1 ms |
344 KB |
Output is correct |
| 3 |
Correct |
0 ms |
348 KB |
Output is correct |
| 4 |
Correct |
1 ms |
344 KB |
Output is correct |
| 5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 6 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
604 KB |
Output is correct |
| 2 |
Correct |
2 ms |
600 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
344 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
344 KB |
Output is correct |
| 2 |
Correct |
1 ms |
344 KB |
Output is correct |
| 3 |
Correct |
0 ms |
348 KB |
Output is correct |
| 4 |
Correct |
1 ms |
344 KB |
Output is correct |
| 5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 6 |
Halted |
0 ms |
0 KB |
- |
