# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
654179 | jiahng | Rectangles (IOI19_rect) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "rect.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pi;
typedef vector <int> vi;
typedef vector <pi> vpi;
typedef pair<pi, ll> pii;
typedef pair <pi,pi> pipi;
typedef set <ll> si;
typedef long double ld;
#define f first
#define s second
#define mp make_pair
#define FOR(i,s,e) for(int i=s;i<=int(e);++i)
#define DEC(i,s,e) for(int i=s;i>=int(e);--i)
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define lbd(x, y) lower_bound(all(x), y)
#define ubd(x, y) upper_bound(all(x), y)
#define aFOR(i,x) for (auto i: x)
#define mem(x,i) memset(x,i,sizeof x)
#define fast ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define maxn 2501
#define INF (ll)1e9
#define MOD 1000000007
typedef pair <vi, int> pvi;
typedef pair <int,pi> ipi;
typedef vector <pii> vpii;
int N,M;
set <pi> hpairs[maxn], vpairs[maxn];
bool intersect(pi x, pi y){
return max(x.f, y.f) <= min(x.s, y.s);
}
struct node{
int s,e,m,num=0;
unordered_map <int,int> fw;
node *l,*r;
node(int ss,int ee){
s = ss; e = ee; m = (s + e) / 2;
if (s != e){
l = new node(s,m); r = new node(m+1,e);
}
}
void insert(int p, int v){
num++;
for (int i = v+1; i <= M; i += i & (-i)) fw[i]++;
if (s == e) return;
if (p > m) r->insert(p,v);
else l->insert(p,v);
}
int qry(int a,int b,int c){ // Number in [a,b] >= c
if (a <= s && e <= b){
int ans = 0;
for (int i = c; i > 0; i -= i & (-i)) ans += fw[i];
return num - ans;
}else if (a > e || s > b) return 0;
else return l->qry(a,b,c) + r->qry(a,b,c);
}
};
vector <pii> B[maxn];
vi C[maxn],D[maxn];
long long count_rectangles(std::vector<std::vector<int> > a) {
N = 5, M = 6;
N = a.size(); M = a[0].size();
FOR(i,0,N-1){
stack <pi> st;
FOR(j,0,M-1){
while (!st.empty() && st.top().f < a[i][j]) st.pop();
if (!st.empty() && j - st.top().s + 1 >= 3) hpairs[i].insert(pi(st.top().s+1, j-1));
st.push(pi(a[i][j], j));
}
while (!st.empty()) st.pop();
DEC(j,M-1,0){
while (!st.empty() && st.top().f < a[i][j]) st.pop();
if (!st.empty() && st.top().s - j + 1 >= 3) hpairs[i].insert(pi(j+1, st.top().s-1));
st.push(pi(a[i][j], j));
}
}
FOR(j,0,M-1){
stack <pi> st;
FOR(i,0,N-1){
while (!st.empty() && st.top().f < a[i][j]) st.pop();
if (!st.empty() && i - st.top().s + 1 >= 3) vpairs[j].insert(pi(st.top().s+1, i-1));
st.push(pi(a[i][j], i));
}
while (!st.empty()) st.pop();
DEC(i,N-1,0){
while (!st.empty() && st.top().f < a[i][j]) st.pop();
if (!st.empty() && st.top().s - i + 1 >= 3) vpairs[j].insert(pi(i+1, st.top().s-1));
st.push(pi(a[i][j], i));
}
}
/*
cout << "HPAIRS: \n";
FOR(i,0,N-1){
cout << "ROW " << i << '\n';
aFOR(j, hpairs[i]) cout << j.f << ' ' << j.s << '\n';
}
cout << "VPAIRS: \n";
FOR(i,0,M-1){
cout << "COL " << i << '\n';
aFOR(j, vpairs[i]) cout << j.f << ' ' << j.s << '\n';
}
*/
vector <pipi> hrects, vrects;
FOR(i,0,N-1){
aFOR(j, hpairs[i]){
int a = i, b = j.f, c = N - 1, d = j.s;
FOR(k,i+1,N-1){
if (hpairs[k].count(j)){
hpairs[k].erase(j);
}else{
c = k - 1;
break;
}
}
hrects.pb(pipi(pi(a,b), pi(c,d)));
}
}
FOR(i,0,M-1){
aFOR(j, vpairs[i]){
int a = j.f, b = i, c = j.s, d = M - 1;
FOR(k,i+1,M-1){
if (vpairs[k].count(j)){
vpairs[k].erase(j);
}else{
d = k - 1;
break;
}
}
vrects.pb(pipi(pi(a,b), pi(c,d)));
}
}
/*
cout << "HRECTS: \n";
aFOR(i, hrects) cout << i.f.f << ' ' << i.f.s << ' ' << i.s.f << ' ' << i.s.s << '\n';
cout << "VRECTS: \n";
aFOR(i, vrects) cout << i.f.f << ' ' << i.f.s << ' ' << i.s.f << ' ' << i.s.s << '\n';
*/
int ans = 0;
aFOR(i, hrects) aFOR(j, vrects){
if (!(i.f.f <= j.f.f && j.s.f <= i.s.f)) continue;
if (!(j.f.s <= i.f.s && i.s.s <= j.s.s)) continue;
//cout << i.f.f << ' ' << i.f.s << ' ' << i.s.f << ' ' << i.s.s << '\n';
//cout << j.f.f << ' ' << j.f.s << ' ' << j.s.f << ' ' << j.s.s << '\n' << '\n';
ans++;
}
return ans;
int ans = 0;
aFOR(i, vrects){
if (i.f.s > 0) B[i.f.s-1].pb(pii(pi(i.f.f, i.s.f), -1));
B[i.s.s].pb(pii(pi(i.f.f, i.s.f), 1));
}
FOR(i,0,hrects.size() - 1){
C[hrects[i].s.s].pb(i);
}
FOR(i,0,hrects.size() - 1){
D[hrects[i].f.s].pb(i);
}
node *seg = new node(0,N-1), *seg2 = new node(0,N-1);
vpi v1,v2;
FOR(i,0,M-1){
aFOR(j,C[i]){
seg->insert(hrects[j].f.f, hrects[j].s.f);
v1.pb(pi(hrects[j].f.f, hrects[j].s.f));
}
aFOR(j, D[i]){
seg2->insert(hrects[j].f.f, hrects[j].s.f);
v2.pb(pi(hrects[j].f.f, hrects[j].s.f));
}
aFOR(j, B[i]){
if (j.s == 1){
aFOR(k, v1) if (k.f <= j.f.f && j.f.s <= k.s) ans++;
//ans += seg->qry(0, j.f.f, j.f.s);
}else{
//ans -= seg2->qry(0,j.f.f,j.f.s);
aFOR(k, v2) if (k.f <= j.f.f && j.f.s <= k.s) ans--;
}
}
}
return ans;
}