Submission #566651

#	Time	Username	Problem	Language	Result	Execution time	Memory
566651		mars4	Harbingers (CEOI09_harbingers)	C++17	100 / 100	112 ms	26728 KiB

harbingers

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp> 

using namespace std;
using namespace __gnu_pbds; 

#define ff              first
#define ss              second
#define ll              int64_t
#define ld              long double
#define nl              cout<<"\n"
#define i128            __int128_t
#define all(v)          v.begin(),v.end()
#define mset(a,v)       memset((a),(v),sizeof(a))
#define forn(i,a,b)     for(int64_t i=int64_t(a);i<int64_t(b);++i)
#define forb(i,a,b)     for(int64_t i=int64_t(a);i>=int64_t(b);--i)
#define fastio()        ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);

#define mod         1'000'000'007
#define mod2        998'244'353 
#define inf         1'000'000'000'000'007
#define pi          3.14159265358979323846

template<class key,class cmp=std::less<key>>
using ordered_set=tree<key,null_type,cmp,rb_tree_tag,tree_order_statistics_node_update>;

template<class L,class R> ostream& operator<<(ostream& out,pair<L,R> &p)        {return out<<"("<<p.ff<<", "<<p.ss<<")";}
template<class T> ostream& operator<<(ostream& out,vector<T> &v)                {out<<"[";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())out<<", ";out<<*it;}return out<<"]";}
template<class T> ostream& operator<<(ostream& out,deque<T> &v)                 {out<<"[";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())out<<", ";out<<*it;}return out<<"]";}
template<class T> ostream& operator<<(ostream& out,set<T> &s)                   {out<<"{";for(auto it=s.begin();it!=s.end();++it){if(it!=s.begin())out<<", ";out<<*it;}return out<<"}";}
template<class T> ostream& operator<<(ostream& out,ordered_set<T> &s)           {out<<"{";for(auto it=s.begin();it!=s.end();++it){if(it!=s.begin())out<<", ";out<<*it;}return out<<"}";}
template<class L,class R> ostream& operator<<(ostream& out,map<L,R> &m)         {out<<"{";for(auto it=m.begin();it!=m.end();++it){if(it!=m.begin())out<<", ";out<<*it;}return out<<"}";}

void dbg_out() {cerr<<"]\n";}
template<typename Head,typename... Tail> 
void dbg_out(Head H,Tail... T) {cerr<<H;if(sizeof...(Tail))cerr<<", ";dbg_out(T...);}
#ifdef LOCAL
#define dbg(...) cerr<<"["<<#__VA_ARGS__<<"] = [",dbg_out(__VA_ARGS__)
#else
#define dbg(...)
#endif

//---------------------------------mars4---------------------------------

struct Line
{
	ll m;
	ll c;

	Line(ll m,ll c):m(m),c(c) {}

	ll eval(ll x)
	{
		return m*x+c;
	}
};

class CHT
{
	const ll logN=20;

	ld intersectX(Line a,Line b)
	{
		return (ld)(a.c-b.c)/(b.m-a.m);
	}

	public:
	vector<Line> cv_hull;
	vector<ll> ind;
	ll sz;

	void init(ll n)
	{
		cv_hull=vector<Line>(n,Line(0,0));
		ind=vector<ll>(n);
		iota(all(ind),0);
	}

	ll get_pos(ll m,ll c)
	{
		Line line(m,c);
		int stk_max=sz;
// check if hull is trivial or if line belongs at the end

	if (stk_max < 2 || 

		intersectX(line, cv_hull[stk_max - 1]) >= intersectX(cv_hull[stk_max - 1], cv_hull[stk_max - 2])) {

		return stk_max;

	}


	// begin at l = 1 because we need to check intersection between k and k - 1

	int l = 1, r = stk_max - 1;

	while (l < r) {

		int m = (l + r) / 2;

		if (intersectX(line, cv_hull[m]) < intersectX(cv_hull[m], cv_hull[m - 1])) {

			r = m;

		} else {

			l = m + 1;

		}

	}

	return l;
	}
	
	ll query(ll x)
	{
		ll cur=*lower_bound(ind.begin(),ind.begin()+sz-1,x,[&](ll i,ll x){
			return intersectX(cv_hull[i],cv_hull[i+1])<x;
		});
		return cv_hull[cur].eval(x);
	}
};

CHT cht;
vector<vector<pair<ll,ll>>> v;
vector<pair<ll,ll>> a;
vector<Line> g;
vector<ll> sz;
vector<ll> ans;

void dfs(ll cur,ll prev,ll dist)
{
	if(cur)
	{
		ans[cur]=cht.query(a[cur].ss)+a[cur].ss*dist+a[cur].ff;
		ll pos=cht.get_pos(-dist,ans[cur]);
		g[cur]=cht.cv_hull[pos];
		sz[cur]=cht.sz;
		cht.cv_hull[pos]=Line(-dist,ans[cur]);
		cht.sz=pos+1;
	}
	for(auto [i,w]:v[cur])
	{
		if(i!=prev)
		{
			dfs(i,cur,dist+w);
		}
	}
	if(cur)
	{
		cht.cv_hull[cht.sz-1]=g[cur];
		cht.sz=sz[cur];
	}
}

int main()
{
	fastio();
	ll z,n,m,t,k,i,j,l,d,h,r;
	cin>>n;
	v=vector<vector<pair<ll,ll>>>(n);
	a=vector<pair<ll,ll>>(n);
	g=vector<Line>(n,Line(0,0));
	sz=vector<ll>(n);
	ans=vector<ll>(n);
	cht.init(n);
	forn(i,0,n-1)
	{
		cin>>l>>r>>d;
		l--,r--;
		v[l].push_back({r,d});
		v[r].push_back({l,d});
	}
	forn(i,1,n)
	{
		cin>>a[i].ff>>a[i].ss;
	}
	cht.cv_hull.push_back({0,0});
	cht.sz=1;
	dfs(0,-1,0);
	forn(i,1,n)
	{
		cout<<ans[i]<<" ";
	}
	nl;
	cerr<<"\nTime elapsed: "<<1000*clock()/CLOCKS_PER_SEC<<"ms\n";
	return 0;
}

Compilation message (stderr)

harbingers.cpp: In function 'int main()':
harbingers.cpp:162:5: warning: unused variable 'z' [-Wunused-variable]
  162 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |     ^
harbingers.cpp:162:9: warning: unused variable 'm' [-Wunused-variable]
  162 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |         ^
harbingers.cpp:162:11: warning: unused variable 't' [-Wunused-variable]
  162 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |           ^
harbingers.cpp:162:13: warning: unused variable 'k' [-Wunused-variable]
  162 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |             ^
harbingers.cpp:162:15: warning: unused variable 'i' [-Wunused-variable]
  162 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |               ^
harbingers.cpp:162:17: warning: unused variable 'j' [-Wunused-variable]
  162 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |                 ^
harbingers.cpp:162:23: warning: unused variable 'h' [-Wunused-variable]
  162 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |                       ^

• Subtask 1: 100 / 100