Submission #895475

#	Time	Username	Problem	Language	Result	Execution time	Memory
895475		thunopro	Two Antennas (JOI19_antennas)	C++14	100 / 100	546 ms	38644 KiB

antennas

#include<bits/stdc++.h>
using namespace std ; 
#define maxn 200009 
#define ll long long 
#define pb push_back 
#define fi first 
#define se second 
#define left id<<1
#define right id<<1|1
#define re exit(0); 
#define _lower(v,x) lower_bound(v.begin(),v.end(),x)-v.begin()+1
#define EXP 1e-6
#define flush mobshigeo 
 
#define YES "YES" 
#define NO "NO" 
#define Yes "Yes" 
#define No "No" 
 
const int mod = 1e9+7 ; 
const int LOG = 19 ; 
const int INF = 1e9 ; 
 
typedef vector<int> vi ; 
typedef pair<int,int> pii ; 
typedef vector<pii> vii ; 
typedef pair<ll,ll> pll ; 
typedef vector<ll> vl ;
 
void add ( int &a , int b )
{
	a += b ; 
	if ( a < 0 ) a += mod ; 
	if ( a >= mod ) a -= mod ; 
}  
 
template < typename T > void chkmin ( T&a , T b ) { if ( a > b ) a = b ; } ; 
template < typename T > void chkmax ( T&a , T b ) { if ( a < b ) a = b ; } ; 
 
void rf () 
{
	freopen ("bai1.inp","r",stdin) ; 
//	freopen ("anten.out","w",stdout) ; 
}
 
int _pow ( int a , int n ) 
{
	if ( n == 0 ) return 1 ; 
	int res = _pow (a,n/2) ; 
	if ( n % 2 ) return (1ll*res*res%mod*a%mod) ; 
	else return (1ll*res*res%mod) ; 
}
 
int n , nq ; 
struct shape {
	int l , r , h ; 
} a [maxn] ;
 
struct ape {
	int ans , h ; 
}T[maxn*4];  
int lazy [maxn*4] ; 
 
void down ( int id ) 
{
	int &t = lazy [id] ; 
	chkmax (T[left].ans,t-T[left].h) ; 
	chkmax (T[right].ans,t-T[right].h) ; 
	chkmax (lazy[left],t) ; 
	chkmax (lazy[right],t) ; 
	t = 0 ; 
}
ape combine ( ape u , ape v )
{
	return {max(u.ans,v.ans),min(u.h,v.h)} ; 
}
void update ( int id , int l , int r , int u , int v , int h , int op ) 
{
	if ( l > v || r < u ) return ; 
	if ( u <= l && r <= v ) 
	{
		if ( op == 1 ) 
		{
			if ( h == 1 ) T [id].h = a[l].h ; 
			else T [id].h = INF ; 
		}
		else 
		{
			chkmax (T[id].ans,h-T[id].h) ;
			chkmax (lazy[id],h) ; 
		}
		return ; 
	}
	int mid = (l+r)/2 ; 
	down (id) ;
	update (left,l,mid,u,v,h,op) ; 
	update (right,mid+1,r,u,v,h,op) ; 
	T [id] = combine (T[left],T[right]) ; 
}
int get ( int id , int l , int r , int u , int v ) 
{
	if ( l > v || r < u ) return - 1 ; 
	if ( u <= l && r <= v ) return T [id].ans ; 
	int mid = (l+r)/2 ; 
	down (id) ; 
	return max (get(left,l,mid,u,v),get(right,mid+1,r,u,v)) ; 
}
 
vii event [maxn] , query [maxn] ; 
int ans [maxn] ; 
 
void reset () 
{
	for ( int i = 0 ; i <= n*4 ; i ++ ) T [i] = {-1,INF} , lazy [i] = 0 ; 
	for ( int i = 1 ; i <= n ; i ++ ) event [i].clear () ; 
}
void solve () 
{
	reset () ; 
	for ( int i = 1 ; i <= n ; i ++ ) 
	{
		int l = a [i].l , r = a [i].r , h = a[i].h ;
		for ( auto x : event [i] ) update (1,1,n,x.fi,x.fi,x.se,1) ;
		int L = max (i-r,1) , R = i-l ; 
		if ( L <= R ) update (1,1,n,L,R,h,2) ;  
	
		for ( auto x : query [i] ) chkmax (ans[x.se],get(1,1,n,x.fi,i) ) ; 
		
		if ( i + l <= n ) event [i+l].pb({i,1}) ; 
		if ( i + r + 1 <= n ) event [i+r+1].pb({i,-1}) ; 
	}
	
 
}
int main () 
{
	ios_base::sync_with_stdio(0) ; 
	cin.tie(0);cout.tie(0) ; 
//	rf () ; 
	cin >> n ; 
	for ( int i = 1 ; i <= n ; i ++ ) cin >> a[i].h >> a [i].l >> a [i].r ; 
	
	cin >> nq ; 
	for ( int i = 1 ; i <= nq ; i ++ ) 
	{
		int l , r ; cin >> l >> r ; 
		query [r] . pb ({l,i}) ; 
	} 
	
	memset ( ans , - 1 , sizeof ans ) ; 
	
	solve () ;
	
	for ( int i = 1 ; i <= n ; i ++ ) a [i].h = INF - a [i].h ; 
	
	solve () ; 
	
	for ( int i = 1 ; i <= nq ; i ++ ) cout << ans [i] << "\n" ;  
}
 
// std=c++11 thunopro 

Compilation message (stderr)

antennas.cpp: In function 'void rf()':
antennas.cpp:42:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |  freopen ("bai1.inp","r",stdin) ;
      |  ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 2 / 2
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 65 / 65