CF877E Danil and a Part-time Job

CF877E Danil and a Part-time Job

树剖然后线段树维护即可,维护取反操作本质就是交换 01 的个数即可。

代码:

#include<bits/stdc++.h>
using namespace std;
template <typename T>
inline void read(T &x){
	x=0;char ch=getchar();bool f=false;
	while(!isdigit(ch)){if(ch=='-'){f=true;}ch=getchar();}
	while(isdigit(ch)){x=(x<<1)+(x<<3)+(ch^48);ch=getchar();}
	x=f?-x:x;
	return ;
}
template <typename T>
inline void write(T x){
	if(x<0) putchar('-'),x=-x;
	if(x>9) write(x/10);
	putchar(x%10^48);
	return ;
}
const int N=2e5+5;
struct TREE{
	struct node{
		int l,r;
		int tag,val;
	}tree[N<<2];
	#define l(x) tree[(x)].l
	#define r(x) tree[(x)].r
	#define mid(x) (tree[(x)].l+tree[(x)].r>>1)
	#define tag(x) tree[(x)].tag
	#define val(x) tree[(x)].val
	#define ls x<<1
	#define rs x<<1|1
	int a[N];
	void pushdown(int x){
		if(tag(x)){
			tag(ls)^=1,val(ls)=r(ls)-l(ls)+1-val(ls);
			tag(rs)^=1,val(rs)=r(rs)-l(rs)+1-val(rs);
			tag(x)=0;
		}
	} 
	void Pushup(int x){
		val(x)=val(ls)+val(rs);
	}
	void build(int x,int l,int r){
		l(x)=l,r(x)=r;tag(x)=0;
		if(l==r){val(x)=a[l];return;}
		build(ls,l(x),mid(x));
		build(rs,mid(x)+1,r(x));
		Pushup(x);
	}
	void Modify(int x,int l,int r){
		if(r<l(x)||r(x)<l)return;
		if(l<=l(x)&&r(x)<=r){
			tag(x)^=1;
			val(x)=r(x)-l(x)+1-val(x);
			return;
		}
		pushdown(x);
		Modify(ls,l,r);
		Modify(rs,l,r);
		Pushup(x);
	}
	int Query(int x,int l,int r){
		if(r<l(x)||r(x)<l)return 0;
		if(l<=l(x)&&r(x)<=r)return val(x);
		pushdown(x);
		return Query(ls,l,r)+Query(rs,l,r); 
	}
}T; 
int n,m,a;
struct Graph{
	struct node{
		int v,nex;
	}e[N<<1];
	int cnt,head[N];
	void add(int x,int y){e[++cnt]=(node){y,head[x]};head[x]=cnt;}
	int tot,dfn[N],siz[N];
	void dfs(int x,int fa){
		dfn[x]=++tot,siz[x]=1;
		for(int i=head[x];i;i=e[i].nex) if(e[i].v!=fa)dfs(e[i].v,x),siz[x]+=siz[e[i].v];
	}
}G;
signed main(){
	read(n);
	for(int i=1;i<n;i++) read(a),G.add(a,i+1);
	G.dfs(1,0);
	for(int i=1;i<=n;i++) read(a),T.a[G.dfn[i]]=a;
	T.build(1,1,n);
	read(m);
	while(m--){
		char op[5];scanf("%s",op);
		int x;read(x);
		if(op[0]=='g'){
			write(T.Query(1,G.dfn[x],G.dfn[x]+G.siz[x]-1));
			putchar('
');	
		}
		else T.Modify(1,G.dfn[x],G.dfn[x]+G.siz[x]-1);
	}
	return 0;
}
原文地址:https://www.cnblogs.com/Akmaey/p/14676970.html