Submission #520814

#	Time	Username	Problem	Language	Result	Execution time	Memory
520814		nathanlee726	Capital City (JOI20_capital_city)	C++14	0 / 100	1393 ms	508080 KiB

capital_city

//#include<i_am_noob_orz>
#include<bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
#define ll long long
//#define int ll
#define ull unsigned long long
#define pii pair<int,int>
#define X first
#define Y second
#define mod ((ll)1e9+7)
#define pb push_back
#define mp make_pair
#define abs(x) ((x)>0?(x):(-(x)))
#define F(n) Fi(i,n)
#define Fi(i,n) Fl(i,0,n)
#define Fl(i,l,n) for(int i=l;i<n;i++)
#define memres(a) memset(a,0,sizeof(a))
#define all(a) a.begin(),a.end()
#define sz(a) ((int)a.size())
#define ceiling(a,b) (((a)+(b)-1)/(b))
#define endl '\n'
#define bit_count(x) __builtin_popcountll((x))
#define ykh mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define jimmy_is_kind false
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> rbtree;
 
//#define LOCAL
#ifdef LOCAL
#define bug(...) cerr<<"#"<<__LINE__<<' '<<#__VA_ARGS__<<"- ", _do(__VA_ARGS__)
template<typename T> void _do(T && x) {cerr<<x<<endl;}
template<typename T, typename ...S> void _do(T && x, S&&...y) {cerr<<x<<", "; _do(y...);}
#define IOS()
#else
#define IOS() ios_base::sync_with_stdio(0), cin.tie(0)
#define endl '\n'
#define bug(...)
#endif
 
int add(int a,int b){return(a+b>=mod?a+b-mod:a+b);}
int sub(int a,int b){return(a<b?a+mod-b:a-b);}
int po(int a,int b){
	if(b==0)return 1;
	if(b==1)return(a%mod);
	int tem=po(a,b/2);
	if(b&1)return(((tem*tem)%mod)*a)%mod;
	else return(tem*tem)%mod; 
}
int GCD(int a,int b){
	int x=0;
	int ra,rb;
	while(a&&b){
		if(((a&1)==0)&&((b&1)==0)){
			a>>=1,b>>=1,x++;
		}
		else if((a^b)&1){
			if(a&1)b>>=1;
			else a>>=1;
		}
		else{
			ra=abs(a-b),rb=min(a,b);
			a=ra,b=rb;
		}
	}
	return max(a,b)<<x;
}
int gcd(int a,int b){if(b==0)return a;return gcd(b,a%b);}
 
int n,k,dep[200010],ord[200010],pa[200010][20],inde=0,ind,id=0,pt[200010][20],co[200010],cnt[5000010],ou[5000010];
vector<int> g[500010],rg[5000010],cl[200010];
 
void dfs(int p,int f,int d){
	dep[p]=d;
	ord[p]=inde++;
	pa[p][0]=f;
	for(int j=0;j<18;j++){if(pa[p][j]!=-1)pa[p][j+1]=pa[pa[p][j]][j];else pa[p][j+1]=-1;}
	if(p!=0){
		pt[p][0]=ind++;
		assert(ind<=5000000);
		rg[pt[p][0]].pb(p);
		rg[pt[p][0]].pb(pa[p][0]);
		for(int j=1;(1ll<<j)<=dep[p];j++){
			pt[p][j]=ind++;
			rg[pt[p][j]].pb(p);
			rg[pt[p][j]].pb(pt[p][j-1]);
			assert(pa[p][j-1]!=-1);
			rg[pt[p][j]].pb(pt[pa[p][j-1]][j-1]);
		}
	}
	for(int u:g[p]){
		if(u==f)continue;
		dfs(u,p,d+1);
	}
}
 
bool cmp(int x,int y){
	return ord[x]<ord[y];
}
 
void ad_ed(int p,int l){
	int tp=p;
	assert(l>=0);
	for(int i=18;i>=0;i--){
		if((1ll<<i)&l)rg[p].pb(pt[tp][i]),tp=pa[tp][i];
	}
}
 
void lca_ed(int x,int y){
	if(x==y)return;
	int rx=x,ry=y;
	int xd=dep[x],yd=dep[y];
	if(xd>yd)swap(x,y),swap(xd,yd),swap(rx,ry);
	int len=yd-xd;
	for(int i=19;i>=0;i--){
		if((1ll<<i)&len)y=pa[y][i];
	}
	int r;
	if(x==y)r=dep[x];
	else{
	for(int i=19;i>=0;i--){
		if(pa[x][i]==-1)continue;
		if(pa[x][i]!=pa[y][i])x=pa[x][i],y=pa[y][i];
	}
	r=pa[x][0];
	r=dep[r];
	}
	int xl=xd-r,yl=yd-r;
	bug(rx,xl,ry,yl);
	if(xl>0)ad_ed(rx,xl);
	if(yl>0)ad_ed(ry,yl);
}
 
vector<int> sta;
int dfn[5000010],low[5000010],ind1=0,gr[5000010];
bool inst[5000010]={0};
 
void tarjan(int p){
	dfn[p]=low[p]=++ind1;
	inst[p]=1;
	sta.pb(p);
	for(int u:rg[p]){
		if(dfn[u]==0){
			tarjan(u);
			low[p]=min(low[p],low[u]);
		}
		else if(inst[u]){
			low[p]=min(low[p],dfn[u]);
		}
	}
	if(low[p]==dfn[p]){
		id++;
		while(sta.back()!=p){
			inst[sta.back()]=0;
			gr[sta.back()]=id;
			bug(id,sta.back());
			sta.pop_back();
		}
		//assert(sta.back()==p);
		inst[p]=0;
		gr[p]=id;
		bug(id,p);
		sta.pop_back();
	}
}
 
signed main(){
	IOS();
	cin>>n>>k;
	F(n-1){
		int x,y;
		cin>>x>>y;
		//x=i+1,y=i+2;
		--x,--y;
		g[x].pb(y);
		g[y].pb(x);
	}
	ind=n;
	dfs(0,-1,0);
	F(n){
		int x;
		cin>>x;
		//x=0;
		--x;
		cl[x].pb(i);
		co[i]=x;
	}
	F(k){
		if(sz(cl[i])>=2){
			sort(all(cl[i]),cmp);
			cl[i].pb(cl[i][0]);
			Fi(j,sz(cl[i])-1){
				bug(cl[i][j],cl[i][j+1]);
				rg[cl[i][j]].pb(cl[i][j+1]);
				lca_ed(cl[i][j],cl[i][j+1]);
			}
		}
	}
	memres(dfn);
	memres(low);
	memres(cnt);
	F(ind){
		if(dfn[i]==0)tarjan(i);
	}
	//memres(out);
	return 0;
	F(ind){
		if(sz(rg[i]))for(int j:rg[i]){
			if(gr[i]!=gr[j]){
				ou[gr[i]]++;
			}
		}
	}
	F(k){
		if(sz(cl[i]))cnt[gr[cl[i][0]]]++;
	}
	/*F(ind){
		bug(i);
		for(int j:rg[i])cout<<j<<" ";
		cout<<endl;
	}*/
	bug(id);
	int ans=n;
	for(int i=1;i<=id;i++)bug(cnt[i],ou[i]);
	for(int i=1;i<=id;i++)if(cnt[i]!=0&&ou[i]==0)ans=min(ans,cnt[i]);
	cout<<ans-1<<endl;
	return 0;
}
/*
10 5
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
5 4 1 3 2 3 2 1 4 5
 
20 10
19 6
6 3
3 18
18 20
20 11
11 7
7 17
17 14
14 9
9 13
13 5
5 12
12 4
4 10
10 2
2 16
16 15
15 8
8 1
8
3
2
6
7
5
7
5
1
1
4
9
4
6
2
10
9
10
8
3
 
20 10
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
10 11
11 12
12 13
13 14
14 15
15 16
16 17
17 18
18 19
19 20
8 5 2 10 3 1 6 9 7 4 1 6 9 7 4 3 10 2 5 8
*/

• Subtask 1: 0 / 1
• Subtask 2: 0 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 59