oj.uz

Submission #836282

# Submission time Handle Problem Language Result Execution time Memory
836282 2023-08-24T09:44:24 Z sunwukong123 Dynamic Diameter (CEOI19_diameter) C++14
100 / 100
 4291 ms 274940 KB 
#include <bits/stdc++.h>
using namespace std;
#define int long long 
void debug_out() {cerr<<endl;}
template <typename Head, typename... Tail>
void debug_out(Head _H, Tail... _T) {cerr<<" "<<to_string(_H);debug_out(_T...);}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:",debug_out(__VA_ARGS__)
const int MAXN = 100005;
const int inf=1000000500ll;
const int oo =1000000000000000000ll;
const int MOD = (int)1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef pair<int,int> pi;
/*
centroid decomposition
construct a segment tree for every tree in every layer
when updating an edge, find all layers that this edge is in
range update that subtree in that tree
range add on that subtree, then, update once, on the root's layer.
hence you can find the diameter passing through the root
by maintaining all such diameters, you can find the diameter of the whole tree
*/
int n,q,w;
int W[MAXN];
vector<pi> adj[MAXN];
int lvl[MAXN];
int sz[MAXN];
int par[MAXN];
int rt;
int st[MAXN][18], en[MAXN][18];
int ctr;
struct node {
	int s,e,m,val,lazy;
	node *l, *r;
	node (int _s, int _e){
		s=_s;e=_e;m=(s+e)/2;
		val=lazy=0;
		if(s!=e){
			l=new node(s,m);
			r=new node(m+1,e);
		}
	}
	int value(){
		if(lazy==0)return val;
		val+=lazy;
		if(s!=e){
			l->lazy+=lazy;
			r->lazy+=lazy;
		}
		lazy=0;
		return val;
	}
	void update(int x, int y, int nval){
		value();
		if(s==x&&e==y){
			lazy+=nval;
			return;
		}
		if(x>m)r->update(x,y,nval);
		else if(y<=m)l->update(x,y,nval);
		else l->update(x,m,nval), r->update(m+1,y,nval);
		val=max(l->value(),r->value()); 
	}
	int query(int x, int y){
		value();
		if(s==x&&e==y)return val;
		if(x>m)return r->query(x,y);
		else if(y<=m)return l->query(x,y);
		else return max(l->query(x,m), r->query(m+1,y));
	}

} *tree[MAXN];
vector<pi> V[MAXN];
multiset<int> L[MAXN];
void pre(int x, int p, int wei){
	for(auto v:adj[x])if(v.first!=p){
		pre(v.first,x,v.second);
	}
}
int dfs1(int x, int p){
	sz[x]=1;
	for(auto v:adj[x])if(v.first!=p){
		if(lvl[v.first] != -1)continue;
		sz[x]+=dfs1(v.first,x);
	}
	return sz[x];
}
int dfs2(int x, int tar, int p){
	for(auto v:adj[x])if(v.first!=p){
		if(lvl[v.first] != -1)continue;
		if(sz[v.first]>tar/2)return dfs2(v.first,tar,x);
	}
	return x;
}
void dfs3(int x, int p, int l){
	st[x][l]=ctr++;
	for(auto v:adj[x])if(v.first!=p){
		if(lvl[v.first] != -1)continue;
		dfs3(v.first,x,l);
	}
	en[x][l]=ctr-1;
}
multiset<int> diams;
void dfs4(int x, int p, int l, int wei){
	if(x!=rt){

		tree[rt]->update(st[x][l],en[x][l],wei);
	}
	for(auto v:adj[x])if(v.first!=p){
		if(lvl[v.first]!=-1)continue;
		dfs4(v.first,x,l,v.second);
	}
}
int getdiam(multiset<int> & s){
	if(s.empty())return 0;
	if(s.size()==1)return *s.begin();

	return *prev(s.end())+*prev(prev(s.end()));
}
void build(int x, int p, int l){

	int sz=dfs1(x,-1);
	int cent=dfs2(x,sz,l);

	if(p==-1)p=cent;
	par[cent]=p;
	lvl[cent]=l;
	rt=cent;
	ctr=0;
	dfs3(cent,-1,l);
	tree[rt]=new node(0,ctr);
	dfs4(cent,-1,l,0);
	for(auto v:adj[cent]){

		if(v.first==p)continue;
		if(lvl[v.first]!=-1)continue;

		V[cent].push_back({en[v.first][l],v.first});
	}
	
	for(auto x:V[cent]){
		int s=tree[rt]->query(st[x.second][l],en[x.second][l]);
		L[rt].insert(s);
	}
	diams.insert(getdiam(L[rt]));

	for(auto v:adj[cent])if(v.first!=p){
		if(lvl[v.first]!=-1)continue;
		build(v.first,cent,l+1);
	}
}
int last;
pi E[MAXN];

int32_t main() 
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin >> n >> q >> w;
	for(int i=0;i<n-1;i++){
		int a,b,c; cin >> a >> b >> c;
		E[i]={a,b};
		W[i]=c;
		adj[a].push_back({b,c});
		adj[b].push_back({a,c});
	}
	pre(1,-1,0);
	memset(lvl,-1,sizeof lvl);
	build(1,-1,0);
	
	while(q--){
		int d,e; cin >> d >> e;
		d=(d+last)%(n-1);
		e=(e+last)%w;


		int cc=e-W[d];
		W[d]=e;
		pair<int,int>nn=min(make_pair(lvl[E[d].first], E[d].first), make_pair(lvl[E[d].second], E[d].second));
		int X=E[d].first, Y=E[d].second;
		int y=nn.second,l=nn.first;
		while(l!=-1){

			if(st[X][l] < st[Y][l])swap(X,Y);
			//update X's subtree

			auto iter=lower_bound(V[y].begin(),V[y].end(),make_pair(st[X][l],0ll));


			int tc=iter->second;

			int lmax=tree[y]->query(st[tc][l],en[tc][l]);
			diams.erase(diams.find(getdiam(L[y])));



			L[y].erase(L[y].find(lmax));

			tree[y]->update(st[X][l],en[X][l],cc);
			lmax=tree[y]->query(st[tc][l],en[tc][l]);
			L[y].insert(lmax); 
			diams.insert(getdiam(L[y]));
			y=par[y];
			--l;
		}
		last=*prev(diams.end());
		cout<<last<<'\n';
	}
}

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 10576 KB Output is correct
2 Correct 5 ms 10452 KB Output is correct
3 Correct 5 ms 10452 KB Output is correct
4 Correct 6 ms 10452 KB Output is correct
5 Correct 5 ms 10452 KB Output is correct
6 Correct 7 ms 10452 KB Output is correct
7 Correct 5 ms 10580 KB Output is correct
8 Correct 5 ms 10580 KB Output is correct
9 Correct 5 ms 10580 KB Output is correct
10 Correct 5 ms 10580 KB Output is correct
11 Correct 5 ms 10580 KB Output is correct
12 Correct 5 ms 10580 KB Output is correct
13 Correct 5 ms 10580 KB Output is correct
14 Correct 6 ms 10580 KB Output is correct
15 Correct 5 ms 10580 KB Output is correct
16 Correct 6 ms 10580 KB Output is correct
17 Correct 6 ms 10580 KB Output is correct
18 Correct 5 ms 10628 KB Output is correct

Subtask #2
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 10576 KB Output is correct
2 Correct 5 ms 10452 KB Output is correct
3 Correct 5 ms 10452 KB Output is correct
4 Correct 6 ms 10452 KB Output is correct
5 Correct 5 ms 10452 KB Output is correct
6 Correct 7 ms 10452 KB Output is correct
7 Correct 5 ms 10580 KB Output is correct
8 Correct 5 ms 10580 KB Output is correct
9 Correct 5 ms 10580 KB Output is correct
10 Correct 5 ms 10580 KB Output is correct
11 Correct 5 ms 10580 KB Output is correct
12 Correct 5 ms 10580 KB Output is correct
13 Correct 5 ms 10580 KB Output is correct
14 Correct 6 ms 10580 KB Output is correct
15 Correct 5 ms 10580 KB Output is correct
16 Correct 6 ms 10580 KB Output is correct
17 Correct 6 ms 10580 KB Output is correct
18 Correct 5 ms 10628 KB Output is correct
19 Correct 20 ms 11860 KB Output is correct
20 Correct 21 ms 11988 KB Output is correct
21 Correct 25 ms 12116 KB Output is correct
22 Correct 27 ms 12244 KB Output is correct
23 Correct 38 ms 17712 KB Output is correct
24 Correct 49 ms 18900 KB Output is correct
25 Correct 56 ms 19752 KB Output is correct
26 Correct 62 ms 20820 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 10452 KB Output is correct
2 Correct 5 ms 10452 KB Output is correct
3 Correct 6 ms 10516 KB Output is correct
4 Correct 16 ms 10832 KB Output is correct
5 Correct 48 ms 11596 KB Output is correct
6 Correct 5 ms 10452 KB Output is correct
7 Correct 6 ms 10836 KB Output is correct
8 Correct 5 ms 10836 KB Output is correct
9 Correct 7 ms 10964 KB Output is correct
10 Correct 19 ms 11092 KB Output is correct
11 Correct 70 ms 12236 KB Output is correct
12 Correct 10 ms 14548 KB Output is correct
13 Correct 10 ms 14548 KB Output is correct
14 Correct 14 ms 14548 KB Output is correct
15 Correct 31 ms 14860 KB Output is correct
16 Correct 104 ms 15980 KB Output is correct
17 Correct 124 ms 91448 KB Output is correct
18 Correct 135 ms 91444 KB Output is correct
19 Correct 130 ms 91500 KB Output is correct
20 Correct 184 ms 91848 KB Output is correct
21 Correct 367 ms 93212 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 12116 KB Output is correct
2 Correct 32 ms 12244 KB Output is correct
3 Correct 126 ms 12752 KB Output is correct
4 Correct 254 ms 13388 KB Output is correct
5 Correct 48 ms 30540 KB Output is correct
6 Correct 77 ms 30668 KB Output is correct
7 Correct 306 ms 31336 KB Output is correct
8 Correct 532 ms 32052 KB Output is correct
9 Correct 195 ms 125652 KB Output is correct
10 Correct 306 ms 125776 KB Output is correct
11 Correct 700 ms 126412 KB Output is correct
12 Correct 1287 ms 127284 KB Output is correct
13 Correct 440 ms 253316 KB Output is correct
14 Correct 566 ms 253356 KB Output is correct
15 Correct 1210 ms 254012 KB Output is correct
16 Correct 1818 ms 254856 KB Output is correct
17 Correct 3396 ms 254708 KB Output is correct

Subtask #5
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 2660 ms 207996 KB Output is correct
2 Correct 2795 ms 213212 KB Output is correct
3 Correct 2685 ms 211512 KB Output is correct
4 Correct 2722 ms 213264 KB Output is correct
5 Correct 2669 ms 204016 KB Output is correct
6 Correct 2414 ms 156852 KB Output is correct
7 Correct 3843 ms 255760 KB Output is correct
8 Correct 3858 ms 255640 KB Output is correct
9 Correct 3822 ms 255792 KB Output is correct
10 Correct 3788 ms 254952 KB Output is correct
11 Correct 3655 ms 243932 KB Output is correct
12 Correct 3293 ms 179568 KB Output is correct
13 Correct 3940 ms 274760 KB Output is correct
14 Correct 4034 ms 274848 KB Output is correct
15 Correct 4119 ms 274940 KB Output is correct
16 Correct 3908 ms 273848 KB Output is correct
17 Correct 3761 ms 260304 KB Output is correct
18 Correct 3306 ms 185360 KB Output is correct
19 Correct 4064 ms 274792 KB Output is correct
20 Correct 3960 ms 274732 KB Output is correct
21 Correct 3913 ms 274916 KB Output is correct
22 Correct 3868 ms 273848 KB Output is correct
23 Correct 4104 ms 260344 KB Output is correct
24 Correct 3512 ms 185384 KB Output is correct

Subtask #6
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 10576 KB Output is correct
2 Correct 5 ms 10452 KB Output is correct
3 Correct 5 ms 10452 KB Output is correct
4 Correct 6 ms 10452 KB Output is correct
5 Correct 5 ms 10452 KB Output is correct
6 Correct 7 ms 10452 KB Output is correct
7 Correct 5 ms 10580 KB Output is correct
8 Correct 5 ms 10580 KB Output is correct
9 Correct 5 ms 10580 KB Output is correct
10 Correct 5 ms 10580 KB Output is correct
11 Correct 5 ms 10580 KB Output is correct
12 Correct 5 ms 10580 KB Output is correct
13 Correct 5 ms 10580 KB Output is correct
14 Correct 6 ms 10580 KB Output is correct
15 Correct 5 ms 10580 KB Output is correct
16 Correct 6 ms 10580 KB Output is correct
17 Correct 6 ms 10580 KB Output is correct
18 Correct 5 ms 10628 KB Output is correct
19 Correct 20 ms 11860 KB Output is correct
20 Correct 21 ms 11988 KB Output is correct
21 Correct 25 ms 12116 KB Output is correct
22 Correct 27 ms 12244 KB Output is correct
23 Correct 38 ms 17712 KB Output is correct
24 Correct 49 ms 18900 KB Output is correct
25 Correct 56 ms 19752 KB Output is correct
26 Correct 62 ms 20820 KB Output is correct
27 Correct 5 ms 10452 KB Output is correct
28 Correct 5 ms 10452 KB Output is correct
29 Correct 6 ms 10516 KB Output is correct
30 Correct 16 ms 10832 KB Output is correct
31 Correct 48 ms 11596 KB Output is correct
32 Correct 5 ms 10452 KB Output is correct
33 Correct 6 ms 10836 KB Output is correct
34 Correct 5 ms 10836 KB Output is correct
35 Correct 7 ms 10964 KB Output is correct
36 Correct 19 ms 11092 KB Output is correct
37 Correct 70 ms 12236 KB Output is correct
38 Correct 10 ms 14548 KB Output is correct
39 Correct 10 ms 14548 KB Output is correct
40 Correct 14 ms 14548 KB Output is correct
41 Correct 31 ms 14860 KB Output is correct
42 Correct 104 ms 15980 KB Output is correct
43 Correct 124 ms 91448 KB Output is correct
44 Correct 135 ms 91444 KB Output is correct
45 Correct 130 ms 91500 KB Output is correct
46 Correct 184 ms 91848 KB Output is correct
47 Correct 367 ms 93212 KB Output is correct
48 Correct 9 ms 12116 KB Output is correct
49 Correct 32 ms 12244 KB Output is correct
50 Correct 126 ms 12752 KB Output is correct
51 Correct 254 ms 13388 KB Output is correct
52 Correct 48 ms 30540 KB Output is correct
53 Correct 77 ms 30668 KB Output is correct
54 Correct 306 ms 31336 KB Output is correct
55 Correct 532 ms 32052 KB Output is correct
56 Correct 195 ms 125652 KB Output is correct
57 Correct 306 ms 125776 KB Output is correct
58 Correct 700 ms 126412 KB Output is correct
59 Correct 1287 ms 127284 KB Output is correct
60 Correct 440 ms 253316 KB Output is correct
61 Correct 566 ms 253356 KB Output is correct
62 Correct 1210 ms 254012 KB Output is correct
63 Correct 1818 ms 254856 KB Output is correct
64 Correct 3396 ms 254708 KB Output is correct
65 Correct 2660 ms 207996 KB Output is correct
66 Correct 2795 ms 213212 KB Output is correct
67 Correct 2685 ms 211512 KB Output is correct
68 Correct 2722 ms 213264 KB Output is correct
69 Correct 2669 ms 204016 KB Output is correct
70 Correct 2414 ms 156852 KB Output is correct
71 Correct 3843 ms 255760 KB Output is correct
72 Correct 3858 ms 255640 KB Output is correct
73 Correct 3822 ms 255792 KB Output is correct
74 Correct 3788 ms 254952 KB Output is correct
75 Correct 3655 ms 243932 KB Output is correct
76 Correct 3293 ms 179568 KB Output is correct
77 Correct 3940 ms 274760 KB Output is correct
78 Correct 4034 ms 274848 KB Output is correct
79 Correct 4119 ms 274940 KB Output is correct
80 Correct 3908 ms 273848 KB Output is correct
81 Correct 3761 ms 260304 KB Output is correct
82 Correct 3306 ms 185360 KB Output is correct
83 Correct 4064 ms 274792 KB Output is correct
84 Correct 3960 ms 274732 KB Output is correct
85 Correct 3913 ms 274916 KB Output is correct
86 Correct 3868 ms 273848 KB Output is correct
87 Correct 4104 ms 260344 KB Output is correct
88 Correct 3512 ms 185384 KB Output is correct
89 Correct 2825 ms 209744 KB Output is correct
90 Correct 3158 ms 227404 KB Output is correct
91 Correct 3731 ms 249008 KB Output is correct
92 Correct 3924 ms 254376 KB Output is correct
93 Correct 4094 ms 262812 KB Output is correct
94 Correct 4117 ms 265212 KB Output is correct
95 Correct 4282 ms 272424 KB Output is correct
96 Correct 4003 ms 271348 KB Output is correct
97 Correct 4045 ms 272188 KB Output is correct
98 Correct 4291 ms 273972 KB Output is correct
99 Correct 3910 ms 272048 KB Output is correct
100 Correct 3944 ms 271868 KB Output is correct