Submission #1107563

#	Time	Username	Problem	Language	Result	Execution time	Memory
1107563		PieArmy	Synchronization (JOI13_synchronization)	C++17	100 / 100	137 ms	19448 KiB

synchronization

typedef long long ll;
ll pie(ll army){return (1ll<<army);}
#include <bits/stdc++.h>
#define fr first
#define sc second
#define pb push_back
#define endl '\n'
#define mid ((left+right)>>1)
const ll inf=2000000000000000005;
const int sonsuz=2000000005;
using namespace std;
ll fpow(ll x,ll y,ll m=0){if(y<0){cout<<"powError";return -1;}if(m)x%=m;ll res=1;while(y>0){if(y&1)res*=x;x*=x;if(m){x%=m;res%=m;}y>>=1;}return res;}

struct Fen{
	int n;
	vector<int>tree,arr;
	void init(int N){
		n=N;
		tree.resize(n+1,0);
		arr.resize(n+1,0);
	}
	void update(int tar){
		int x=((arr[tar]^1)-arr[tar]);
		arr[tar]^=1;
		while(tar<=n){
			tree[tar]+=x;
			tar+=(tar&-tar);
		}
	}
	int qu(int tar){
		int res=0;
		while(tar){
			res+=tree[tar];
			tar-=(tar&-tar);
		}
		return res;
	}
	int query(int l,int r){
		return qu(r)-qu(l-1);
	}
};

int n,m,q;
Fen fen;
int tim=1;
int par[100001],ord[100001],nodes[100001],state[100001],sub[100001],lower[100001],pre[100001];
int ans[100001],old[100001];
vector<pair<int,int>>komsu[100001];

int find_par(int pos){
	while(true){
		if(state[pos]==0){
			return pos;
		}
		if(fen.query(ord[par[pos]],ord[pos])!=ord[pos]-ord[par[pos]]+1){
			int l=ord[par[pos]]+1,r=ord[pos];
			while(l<r){
				int mi=(l+r)/2;
				if(fen.query(mi,ord[pos])==ord[pos]-mi+1){
					r=mi;
				}
				else l=mi+1;
			}
			return pre[nodes[l]];
		}
		pos=pre[par[pos]];
	}
}

void dfs1(int pos){
	sub[pos]=1;
	for(auto x:komsu[pos]){
		if(sub[x.fr])continue;
		lower[x.sc]=x.fr;
		dfs1(x.fr);
		sub[pos]+=sub[x.fr];
	}
}

void dfs2(int pos){
	int mx=-1;
	for(auto x:komsu[pos]){
		if(ord[x.fr])continue;
		if(mx==-1||sub[x.fr]>sub[mx])mx=x.fr;
	}
	if(mx==-1)return;
	ord[mx]=tim++;
	nodes[ord[mx]]=mx;
	pre[mx]=pos;
	par[mx]=par[pos];
	dfs2(mx);
	for(auto x:komsu[pos]){
		if(ord[x.fr])continue;
		ord[x.fr]=tim++;
		pre[x.fr]=pos;
		par[x.fr]=x.fr;
		nodes[ord[x.fr]]=x.fr;
		dfs2(x.fr);
	}
}

void code(){
	cin>>n>>m>>q;
	for(int i=1;i<n;i++){
		int x,y;cin>>x>>y;
		komsu[x].pb({y,i});
		komsu[y].pb({x,i});
	}
	fen.init(n);
	ord[1]=tim++;
	par[1]=1;
	nodes[ord[1]]=1;
	dfs1(1);
	dfs2(1);
	for(int i=1;i<=n;i++){
		ans[i]=1;
	}
	for(int i=1;i<=m;i++){
		int x;cin>>x;
		x=lower[x];
		if(state[x]==0){
			fen.update(ord[x]);
			state[x]^=1;
			int u=find_par(x);
			ans[u]+=ans[x]-old[x];
			old[x]=ans[x];
		}
		else{
			int u=find_par(x);
			ans[x]=old[x]=ans[u];
			fen.update(ord[x]);
			state[x]^=1;
		}
	}
	for(int i=1;i<=n;i++){
		if(state[i]){
			int u=find_par(i);
			ans[i]=old[i]=ans[u];
			fen.update(ord[i]);
			state[i]^=1;
		}
	}
	while(q--){
		int x;cin>>x;
		cout<<ans[x]<<endl;
	}
}

int main(){
	ios_base::sync_with_stdio(false);cin.tie(NULL);
	bool usaco=0;if(usaco){freopen(".in","r",stdin);freopen(".out","w",stdout);}
	int t=1;
	if(!t)cin>>t;
	while(t--){code();cout<<endl;}
	return 0;
}

Compilation message (stderr)

synchronization.cpp: In function 'int main()':
synchronization.cpp:151:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  151 |  bool usaco=0;if(usaco){freopen(".in","r",stdin);freopen(".out","w",stdout);}
      |                         ~~~~~~~^~~~~~~~~~~~~~~~~
synchronization.cpp:151:57: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  151 |  bool usaco=0;if(usaco){freopen(".in","r",stdin);freopen(".out","w",stdout);}
      |                                                  ~~~~~~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 10 / 10
• Subtask 4: 20 / 20
• Subtask 5: 40 / 40