倍增LCA树上差分求调 全WA求调
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倍增LCA树上差分求调 全WA求调
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hao12345ia楼主2025/6/22 14:06
#include<bits/stdc++.h>
using namespace std;
int pre[500001][20],deep[500001];
int n,root;
int f[500001];
vector<int> e[500001];
int diff[500001],sum[500001];
void dfs(int x,int fa){
	pre[x][0]=fa;
//	cout<<x<<endl;
	for(int i:e[x]){
		if(fa==i){
			continue;
		}
		deep[i]=deep[x]+1;
		dfs(i,x);
	}
}
int lca(int u,int v){
	if(deep[u]<deep[v]){
		swap(u,v);
	}
	int up=-1;
	while((1<<(up+1))<=deep[u]){
		up++;
	}
	for(int i=up;i>=0;i--){
		if(deep[u]-(1<<i)>=deep[v]){
			u=pre[u][i];
		}
	}
	if(u==v){
		return u;
	}
	for(int i=up;i>=0;i--){
		if(pre[u][i]!=pre[v][i]){
			u=pre[u][i];
			v=pre[v][i];
		}
	}
	return pre[u][0];
}
void dfs1(int x,int fa){
	for(int i:e[x]){
		if(i!=fa){
			dfs1(i,x);
			diff[x]+=diff[i];
		}
	}
}
int q[500001];
int main(){
	freopen("P3258_1.in","r",stdin);
	freopen("1.out","w",stdout);
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>q[i];
	}
	for(int i=1;i<n;i++){
		int x,y;
		cin>>x>>y;
		e[x].push_back(y);
		e[y].push_back(x);
	}
	dfs(1,0);
	for(int l=1;(1<<l)<=n;l++){
		for(int i=1;i<=n;i++){
			pre[i][l]=pre[pre[i][l-1]][l-1];
		}
	}
	for(int i=1;i<n;i++){
		int l=lca(q[i],q[i+1]);
		diff[q[i]]++;
		diff[q[i+1]]++;
		diff[l]--;
		diff[pre[l][0]]--;
	}
	dfs1(1,0);
	for(int i=2;i<=n;i++){
		diff[q[i]]--;
	}
	for(int i=1;i<=n;i++){
		cout<<diff[i]<<" ";
	}
}
2025/6/22 14:06
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