Codeforces Round #442 (Div. 2) E. Danil and a Part-time Job【线段树+dfs序】

/* ***********************************************
Author        :xiang578
Email         :i@xiang578.com
Created Time  :Mon Nov  6 14:30:42 2017
File Name     :cf877e.cpp
************************************************ */

#include <stdio.h>
#include <string.h>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <math.h>
#include <stdlib.h>
#include <time.h>
using namespace std;
const int n=400000+10;
int N,sum[4*n],lazy[4*n],in
,out
,a
,mp
,cnt;
vector<int>g
;

void dfs(int x)
{
in[x]=++cnt;
mp[cnt]=x;
for(int i=0;i<g[x].size();i++)
dfs(g[x][i]);
out[x]=cnt;
}

void build(int rt,int l,int r)
{
lazy[rt]=0;
if(l==r) {sum[rt]=a[mp[l]];}
else {
int mid = (l+r)/2;
build(rt*2,l,mid);
build(rt*2+1,mid+1,r);
sum[rt]=sum[rt*2]+sum[rt*2+1];
}
}

void pushdown(int rt,int l,int r)
{
lazy[rt]=0;
int mid=(l+r)/2;
sum[rt*2]=mid-l+1-sum[rt*2];
sum[rt*2+1]=r-(mid+1)+1-sum[rt*2+1];
lazy[rt*2]^=1;
lazy[rt*2+1]^=1;
}

int query(int rt,int l,int r,int ql,int qr)
{
if(l>=ql&&r<=qr)
{
return sum[rt];
}
else
{
int mid = (l+r)/2;
if(lazy[rt]) pushdown(rt,l,r);
int ret=0;
if(mid>=ql) ret+=query(rt*2,l,mid,ql,qr);
if(mid+1<=qr) ret+=query(rt*2+1,mid+1,r,ql,qr);
return ret;
}
}

void change(int rt,int l,int r,int ql,int qr)
{

if(l>=ql&&qr>=r)
{
sum[rt]=r-l+1-sum[rt];
lazy[rt]^=1;
}
else{
int mid = (l+r)/2;
if(lazy[rt]) pushdown(rt,l,r);
if(mid>=ql) change(rt*2,l,mid,ql,qr);
if(mid+1<=qr) change(rt*2+1,mid+1,r,ql,qr);
sum[rt]=sum[rt*2]+sum[rt*2+1];
}
}

int main()
{
//freopen("in.txt","r",stdin);
//freopen("out.txt","w",stdout);
cnt=0;
scanf("%d",&N);
for(int i=2;i<=N;i++)
{
int t;
scanf("%d",&t);
g[t].push_back(i);
}
dfs(1);
for(int i=1;i<=N;i++)
{
scanf("%d",a+i);
}
build(1,1,N);
int m;
scanf("%d",&m);
while(m--)
{
char s[10];
int c;
scanf("%s%d",s,&c);
if(s[0]=='g')
{
//printf("%d %d\n",in[c],out[c]);
printf("%d\n",query(1,1,N,in[c],out[c]));
}
else
{
//printf("%d %d\n",in[c],out[c]);
change(1,1,N,in[c],out[c]);
}
}
return 0;
}