Submission #488816

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
488816	2021-11-20T14:44:06 Z	cfalas	Dynamic Diameter (CEOI19_diameter)	C++14	0 / 100	5000 ms	31600 KB

diameter

#include<bits/stdc++.h>
using namespace std;
#define mp make_pair
#define INF 10000000
#define MOD 1000000007
#define MID ((l+r)/2)
#define HASHMOD 2305843009213693951
#define ll long long
#define ull unsigned long long
#define F first
#define S second
typedef pair<ll, ll> ii;
typedef pair<ii, ll> iii;
typedef vector<ll> vi;
typedef vector<ii> vii;
typedef map<int, int> mii;

#define EPS 1e-6
#define FOR(i,n) for(int i=0;i<((int)(n));i++)
#define FORi(i,a,b) for(int i=((int)(a));i<((int)(b));i++)
#define FOA(v, a) for(auto v : a)

int t, n;
vi a, b;

vector<vii> adj;

ii f;

int cnt=0;
vector<int> dfso;
void dfs(int s, int p=-1, ll d=0){
	dfso[s] = cnt++;
	if(d>f.F) f = max(f, {d, s});
	FOA(v, adj[s]){
		if(v.F!=p) dfs(v.F, s, d+v.S);
	}
}

vector<int> pr;

struct node{
	ii l1={0,0}, l2={0,0};
	int w=0;
	int id=1;
	vector<node*> c;
	vector<node*> all_c;

	void build(int p=-1){
		pr.push_back(id);
		FOA(v,adj[id]){
			if(v.F!=p){
				c.push_back(new node());
				c[c.size()-1]->w = v.S;
				c[c.size()-1]->id = v.F;
				c[c.size()-1]->build(id);
			}
		}
		FOA(v, c){
			if(v->w + v->l1.F > l1.F) l2 = l1, l1 = {v->l1.F + v->w, v->id};
			else if(v->w + v->l1.F > l2.F && v->id != l1.S) l2 = {v->l1.F + v->w, v->id};
			//else if(v->w + v->l2 > l2) l2 = v->l2 + v->w;
		}
		//cout<<id<<" ("<<l1.F<<" "<<l1.S<<") ("<<l2.F<<" "<<l2.S<<")"<<endl;
	}

	void update(int s, int t){
		int pos = c.size()-1;
		FOR(i,c.size()-1){
			if(dfso[c[i]->id] <= dfso[s] && dfso[s] < dfso[c[i+1]->id]) pos = i;
		}
		if(s==id){
			//cout<<"CHAINGE "<<s<<endl;
			w = t;
		}
		else{
			c[pos]->update(s, t);
			//node*v = c[pos];
			l1 = {0,0}, l2 = {0,0};
			FOA(v, c){
				if(v->w + v->l1.F > l1.F) l2 = l1, l1 = {v->l1.F + v->w, v->id};
				else if(v->w + v->l1.F > l2.F && v->id != l1.S) l2 = {v->l1.F + v->w, v->id};
				//else if(v->w + v->l2 > l2) l2 = v->l2 + v->w;
			}
			/*
			if(v->id == l1.S) l1.F = v->l1.F + w;
			if(v->w + v->l1.F > l1.F) l2 = l1, l1 = {v->l1.F + v->w, v->id};
			else if(v->w + v->l1.F > l2.F && v->id != l1.S) l2 = {v->l1.F + v->w, v->id};*/
			//cout<<id<<" ("<<l1.F<<" "<<l1.S<<") ("<<l2.F<<" "<<l2.S<<")"<<endl;
		}
	}
};

int main(){
	int q;
	ll w;
	cin>>n>>q>>w;
	adj.assign(n+1, vii());
	dfso.assign(n+1, 0);

	vector<pair<ii,ii> > edg(n-1);
	set<ii> ws;
	vi wu(n);
	FOR(i,n-1){
		ll a, b, c;
		cin>>a>>b>>c;
		ws.insert({-c, i});
		wu[i] = c;
		edg[i] = {{a, adj[a].size()}, {b, adj[b].size()}};
		adj[a].push_back({b,c});
		adj[b].push_back({a,c});
	}
	node root;
	root.build();
	ll last=0;
	dfs(1);
	//FOR(i,n) cout<<dfso[i+1]<<" ";
	//cout<<endl;
	while(q--){
		ll a, b;
		cin>>a>>b;
			//cout<<"UPDATE\n";
		a= (a + last) % (n-1);
		b = (b+last) % w;

		adj[edg[a].F.F][edg[a].F.S].S = b;
		adj[edg[a].S.F][edg[a].S.S].S = b;

		f = {0,1};
		//dfs(1);
		//dfs(f.S);


		root.update(max(ii(dfso[edg[a].F.F], edg[a].F.F),ii(dfso[edg[a].S.F], edg[a].S.F)).S, b);


		//last = f.F;
		last = root.l1.F + root.l2.F;
		cout<<last<<endl;

	}
}

Subtask #1
0 / 11.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	0 ms	204 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #2
0 / 13.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	0 ms	204 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #3
0 / 7.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	1 ms	204 KB	Output is correct
3	Correct	4 ms	204 KB	Output is correct
4	Correct	35 ms	492 KB	Output is correct
5	Correct	171 ms	636 KB	Output is correct
6	Correct	0 ms	204 KB	Output is correct
7	Correct	1 ms	332 KB	Output is correct
8	Correct	1 ms	332 KB	Output is correct
9	Correct	7 ms	452 KB	Output is correct
10	Correct	63 ms	492 KB	Output is correct
11	Correct	304 ms	856 KB	Output is correct
12	Correct	6 ms	1612 KB	Output is correct
13	Correct	9 ms	1740 KB	Output is correct
14	Correct	44 ms	1732 KB	Output is correct
15	Correct	394 ms	1808 KB	Output is correct
16	Correct	1881 ms	2228 KB	Output is correct
17	Correct	151 ms	28460 KB	Output is correct
18	Correct	338 ms	28420 KB	Output is correct
19	Correct	2444 ms	28572 KB	Output is correct
20	Execution timed out	5092 ms	28568 KB	Time limit exceeded
21	Halted	0 ms	0 KB	-