oj.uz

Submission #501419

# Submission time Handle Problem Language Result Execution time Memory
501419 2022-01-03T07:55:39 Z jamezzz 3D Histogram (COCI20_histogram) C++17
110 / 110
 689 ms 250368 KB 
#include <bits/stdc++.h>
using namespace std;
 
#ifdef DEBUG
#define dbg(...) printf(__VA_ARGS__);
#define getchar_unlocked getchar
#else
#define dbg(...)
#endif
#define sf scanf
#define pf printf
#define fi first
#define se second
#define pb push_back
#define sz(x) (int)x.size()
#define mnto(x,y) x=min(x,(__typeof__(x))y)
#define mxto(x,y) x=max(x,(__typeof__(x))y)
#define INF 1023456789
#define LINF 1023456789123456789
#define all(x) x.begin(), x.end()
#define disc(x) sort(all(x));x.resize(unique(all(x))-x.begin());
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<ll, ll> pll;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<pll> vll;
mt19937 rng(time(0));
 
#define mod 1000000007
 
inline int add(int a,int b){
	int r=a+b;
	while(r>=mod)r-=mod;
	while(r<0)r+=mod;
	return r;
}
 
inline int mult(int a,int b){
	return (int)(((ll)(a*b))%mod);
}
 
inline int rd(){
	int x=0;
	char ch=getchar_unlocked();
	while(!(ch&16))ch=getchar();//keep reading while current character is whitespace
    while(ch&16){//this will break when ‘\n’ or ‘ ‘ is encountered
		x=(x<<3)+(x<<1)+(ch&15);
		ch=getchar_unlocked();
	}
	return x;
}
 
struct node{
	int s,e,m;ll v;
	node *l,*r;
	node(int _s,int _e){
		s=_s;e=_e;m=(s+e)/2;v=0;
		if(s!=e)l=new node(s,m),r=new node(m+1,e);
	}
	void up(int x,ll nv){
		if(s==x&&e==x){mxto(v,nv);return;}
		if(x<=m)l->up(x,nv);
		else r->up(x,nv);
		v=max(l->v,r->v);
	}
	ll qry(int x,int y){
		if(s==x&&e==y)return v;
		if(y<=m)return l->qry(x,y);
		if(x>m)return r->qry(x,y);
		return max(l->qry(x,m),r->qry(m+1,y));
	}
}*aseg=new node(1,200005),*bseg=new node(1,200005);
 
struct line{
	ll m,c;
	line(ll _m,ll _c){m=_m;c=_c;}
	ll get(ll x){return m*x+c;}
};
 
struct lct{
	int s,e,m;
	line val=line(0,-INF);
	lct *l=nullptr,*r=nullptr;
	lct(int _s,int _e){
		s=_s;e=_e;m=(s+e)/2;
	}
	void up(line i){
		bool lo=i.get(s)>val.get(s);
		bool mi=i.get(m)>val.get(m);
		bool hi=i.get(e)>val.get(e);
		if(mi)swap(i,val);
		if(e-s==1||i.c==LINF||lo==hi)return;
		if(lo!=mi){
			if(l==nullptr)l=new lct(s,m);
			l->up(i);
		}
		else{
			if(r==nullptr)r=new lct(m,e);
			r->up(i);
		}
	}
	ll qry(ll i){
		if(s+1==e)return val.get(i);
		if(i<m&&l!=nullptr)return max(l->qry(i),val.get(i));
		else if(r!=nullptr)return max(r->qry(i),val.get(i));
		return val.get(i);
	}
};
 
#define maxn 200005
 
int n,a[maxn],b[maxn],al[maxn],ar[maxn],bl[maxn],br[maxn];
stack<int> s;
vi arange[maxn],brange[maxn];
vii aqry[maxn],bqry[maxn];
ll ans=0;
 
void dnc(int l,int r){
	if(l==r)return;
	int m=(l+r)/2;
	dnc(l,m);dnc(m+1,r);
	lct *alct=new lct(1,maxn);
	lct *blct=new lct(1,maxn);
	int ptr=sz(bqry[m+1])-1;
	for(int i=sz(aqry[l])-1;i>=0;--i){
		while(ptr>=0&&bl[bqry[m+1][ptr].se]>=al[aqry[l][i].se]){
			int j=bqry[m+1][ptr].se;
			blct->up({b[j],-(ll)(bl[j]-1)*b[j]});
			--ptr;
		}
		int j=aqry[l][i].se;
		mxto(ans,blct->qry(ar[j])*a[j]);
	}
	ptr=sz(aqry[m+1])-1;
	for(int i=sz(bqry[l])-1;i>=0;--i){
		while(ptr>=0&&al[aqry[m+1][ptr].se]>=bl[bqry[l][i].se]){
			int j=aqry[m+1][ptr].se;
			alct->up({a[j],-(ll)(al[j]-1)*a[j]});
			--ptr;
		}
		int j=bqry[l][i].se;
		mxto(ans,alct->qry(br[j])*b[j]);
	}
	
	vii tmp;
	tmp.resize(sz(aqry[l])+sz(aqry[m+1]));
	merge(all(aqry[l]),all(aqry[m+1]),tmp.begin());
	swap(tmp,aqry[l]);tmp.clear();
	tmp.resize(sz(bqry[l])+sz(bqry[m+1]));
	merge(all(bqry[l]),all(bqry[m+1]),tmp.begin());
	swap(tmp,bqry[l]);tmp.clear();
}
 
int main(){
	sf("%d",&n);
	for(int i=1;i<=n;++i){
		sf("%d%d",&a[i],&b[i]);
	}
	
	s.push(0);
	for(int i=1;i<=n;++i){
		while(!s.empty()&&a[s.top()]>=a[i])s.pop();
		al[i]=s.top()+1;
		arange[al[i]].pb(i);
		s.push(i);
	}
	while(!s.empty())s.pop();
	s.push(0);
	for(int i=1;i<=n;++i){
		while(!s.empty()&&b[s.top()]>=b[i])s.pop();
		bl[i]=s.top()+1;
		brange[bl[i]].pb(i);
		s.push(i);
	}
	while(!s.empty())s.pop();
	s.push(n+1);
	for(int i=n;i>=1;--i){
		while(!s.empty()&&a[s.top()]>=a[i])s.pop();
		ar[i]=s.top()-1;
		aqry[ar[i]].pb({al[i],i});
		s.push(i);
	}
	while(!s.empty())s.pop();
	s.push(n+1);
	for(int i=n;i>=1;--i){
		while(!s.empty()&&b[s.top()]>=b[i])s.pop();
		br[i]=s.top()-1;
		bqry[br[i]].pb({bl[i],i});
		s.push(i);
	}
	while(!s.empty())s.pop();
	
	for(int i=1;i<=n;++i){
		sort(all(aqry[i]));
		sort(all(bqry[i]));
	}
	
	for(int i=n;i>=1;--i){
		for(int j:arange[i]){
			aseg->up(ar[j],(ll)(ar[j]-al[j]+1)*a[j]);
		}
		for(int j:brange[i]){
			bseg->up(br[j],(ll)(br[j]-bl[j]+1)*b[j]);
		}
		for(int j:arange[i]){
			mxto(ans,bseg->qry(al[j],ar[j])*a[j]);
		}
		for(int j:brange[i]){
			mxto(ans,aseg->qry(bl[j],br[j])*b[j]);
		}
	}
	
	dnc(1,n);
	
	pf("%lld\n",ans);
}

Compilation message

histogram.cpp: In function 'int main()':
histogram.cpp:159:4: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  159 |  sf("%d",&n);
      |    ^
histogram.cpp:161:5: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  161 |   sf("%d%d",&a[i],&b[i]);
      |     ^

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 42 ms 57796 KB Output is correct
2 Correct 44 ms 57668 KB Output is correct
3 Correct 51 ms 57484 KB Output is correct
4 Correct 40 ms 57452 KB Output is correct
5 Correct 40 ms 57428 KB Output is correct
6 Correct 42 ms 57924 KB Output is correct
7 Correct 41 ms 57564 KB Output is correct
8 Correct 40 ms 57424 KB Output is correct
9 Correct 40 ms 57556 KB Output is correct
10 Correct 41 ms 57504 KB Output is correct
11 Correct 38 ms 56636 KB Output is correct
12 Correct 42 ms 57924 KB Output is correct

Subtask #2
90.0 / 90.0

# Verdict Execution time Memory Grader output
1 Correct 42 ms 57796 KB Output is correct
2 Correct 44 ms 57668 KB Output is correct
3 Correct 51 ms 57484 KB Output is correct
4 Correct 40 ms 57452 KB Output is correct
5 Correct 40 ms 57428 KB Output is correct
6 Correct 42 ms 57924 KB Output is correct
7 Correct 41 ms 57564 KB Output is correct
8 Correct 40 ms 57424 KB Output is correct
9 Correct 40 ms 57556 KB Output is correct
10 Correct 41 ms 57504 KB Output is correct
11 Correct 38 ms 56636 KB Output is correct
12 Correct 42 ms 57924 KB Output is correct
13 Correct 689 ms 250368 KB Output is correct
14 Correct 383 ms 180968 KB Output is correct
15 Correct 466 ms 157252 KB Output is correct
16 Correct 451 ms 158272 KB Output is correct
17 Correct 416 ms 170560 KB Output is correct
18 Correct 372 ms 147616 KB Output is correct
19 Correct 369 ms 142904 KB Output is correct
20 Correct 393 ms 148460 KB Output is correct
21 Correct 460 ms 158568 KB Output is correct
22 Correct 425 ms 175596 KB Output is correct
23 Correct 94 ms 71920 KB Output is correct
24 Correct 308 ms 176824 KB Output is correct