RT，该怎么改啊QAQ，我太菜了

#include<bits/stdc++.h>
#define int long long
#define MAXN 1000001
using namespace std;
struct node
{
	int l,r;
	int val;
}tree[MAXN];
int n,ans;
inline int read()
{
	int ans=0,flag=1;char ch=getchar();
	while(!isdigit(ch)){if(ch=='-')flag=-1;ch=getchar();}
	while(isdigit(ch))ans=(ans<<3)+(ans<<1)+(ch^48),ch=getchar();
	return ans*flag;
}
inline string reads()
{
	string ans="";char ch=getchar();
	while(!isdigit(ch)&&!isalpha(ch))ch=getchar();
	while(isdigit(ch)||isalpha(ch))ans+=ch,ch=getchar();
	return ans;
}
inline char readc()
{
	char ch=getchar();
	while(!isalpha(ch))ch=getchar();
	return ch;
}
bool check(int l,int r)
{
	if(l==-1&&r==-1) return 1;
	if(l==-1||r==-1) return 0;
	if(tree[l].val!=tree[r].val) return 0;
	return check(tree[l].l,tree[r].r)&&check(tree[l].r,tree[r].l);
}
int get_cnt(int now)
{
	if(tree[now].l==-1&&tree[now].r==-1) return 1;
	return get_cnt(tree[now].l)+get_cnt(tree[now].r)+1;
}
signed main()
{
	n=read();
	for(int i=1;i<=n;i++) tree[i].val=read();
	for(int i=1;i<=n;i++) tree[i].l=read(),tree[i].r=read();
	for(int i=1;i<=n;i++)
	{
	//	printf("i:%d\n",i);
		if(check(i,i))
			ans=max(ans,get_cnt(i));
	}
	printf("%lld",ans);
	return 0;
}