Submission #251990

#	Time	Username	Problem	Language	Result	Execution time	Memory
251990		errorgorn	Dynamic Diameter (CEOI19_diameter)	C++14	31 / 100	336 ms	34808 KiB

diameter

//雪花飄飄北風嘯嘯
//天地一片蒼茫

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
#define ll long long
#define ii pair<ll,ll>
#define iii pair<ii,ll>
#define fi first
#define se second
#define endl '\n'
#define debug(x) cout << #x << " is " << x << endl;

#define rep(x,start,end) for(auto x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)(x).size()

ll MAX(ll a){return a;}
ll MIN(ll a){return a;}
template<typename... Args>
ll MAX(ll a,Args... args){return max(a,MAX(args...));}
template<typename... Args>
ll MIN(ll a,Args... args){return min(a,MIN(args...));}

#define indexed_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

struct node{
	int s,e,m;
	ii val;
	ll lazy=0;
	node *l,*r;
	
	node (int _s,int _e){
		s=_s,e=_e,m=s+e>>1;
		val=ii(0,s);
		
		if (s!=e){
			l=new node(s,m);
			r=new node(m+1,e);
		}
	}
	
	void propo(){
		if (lazy){
			val.fi+=lazy;
			
			if (s!=e){
				l->lazy+=lazy;
				r->lazy+=lazy;
			}
			
			lazy=0;
		}
	}
	
	void update(int i,int j,ll k){
		if (s==i && e==j) lazy+=k;
		else{
			if (j<=m) l->update(i,j,k);
			else if (m<i) r->update(i,j,k);
			else l->update(i,m,k),r->update(m+1,j,k);
			
			l->propo(),r->propo();
			val=max(l->val,r->val);
		}
	}
	
	ii query(int i,int j){
		propo();
		
		if (s==i && e==j) return val;
		else if (j<=m) return l->query(i,j);
		else if (m<i) return r->query(i,j);
		else return max(l->query(i,m),r->query(m+1,j));
	}
} *root=new node(0,100005);

ll n,q,w;
vector<ii> al[100005];
ll cw[100005];
ii range[100005];
ii subtree[100005];

int TIME=1;
ii dfs(int i,int p){
	ii r=ii(1e9,-1e9);
	
	for (auto &it:al[i]){
		if (it.fi==p) continue;
		
		auto temp=dfs(it.fi,i);
		
		if (i==1){
			rep(x,temp.fi,temp.se+1) subtree[x]=temp;
		}
		
		range[it.se]=temp;
		r.fi=min(r.fi,temp.fi);
		r.se=max(r.se,temp.se);
	}
	
	if (r==ii(1e9,-1e9)){
		r=ii(TIME,TIME);
		TIME++;
	}
	
	return r;
}

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	
	cin>>n>>q>>w;
	
	ll a,b,c;
	rep(x,0,n-1){
		cin>>a>>b>>c;
		
		al[a].push_back(ii(b,x));
		al[b].push_back(ii(a,x));
		cw[x]=c;
	}
	
	dfs(1,-1);
	
	rep(x,0,n-1){
		//cout<<range[x].fi<<" "<<range[x].se<<endl;
		root->update(range[x].fi,range[x].se,cw[x]);
	}
	
	ll last=0;
	ll d,e;
	while (q--){
		cin>>d>>e;
		
		d=(d+last)%(n-1);
		e=(e+last)%w;
		
		//cout<<d<<" "<<e<<endl;
		
		root->update(range[d].fi,range[d].se,e-cw[d]);
		cw[d]=e;
		
		auto temp=root->query(0,100005);
		last=temp.fi+max(root->query(0,subtree[temp.se].fi-1),root->query(subtree[temp.se].se+1,100005)).fi;
		
		cout<<last<<endl;
	}
}

Compilation message (stderr)

diameter.cpp: In constructor 'node::node(int, int)':
diameter.cpp:41:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   s=_s,e=_e,m=s+e>>1;
               ~^~

• Subtask 1: 0 / 11
• Subtask 2: 0 / 13
• Subtask 3: 7 / 7
• Subtask 4: 0 / 18
• Subtask 5: 24 / 24
• Subtask 6: 0 / 27