//by szh
#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pii pair<int,int>
#define pll pair<long long,long long>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl
#define pq priority_queue
#define inf 0x3f
#define rep(i,a,b) for (int i=a;i<(b);i++)
#define MP make_pair
#define SZ(x) (int(x.size()))
#define ll long long
#define mod 1000002022
#define ALL(x) x.begin(),x.end()
void inc(int &a,int b) {a=(a+b)%mod;}
void dec(int &a,int b) {a=(a-b+mod)%mod;}
int lowbit(int x) {return x&(-x);}
ll p0w(ll base,ll p) {ll ret=1;while(p>0){if (p%2ll==1ll) ret=ret*base%mod;base=base*base%mod;p/=2ll;}return ret;}
#include "circuit.h"
const int maxn = 2010;
int a[maxn];
vector <int> edge[maxn];
void init(int N, int M, std::vector<int> P, std::vector<int> A) {
rep(i,1,SZ(P)) {
edge[P[i]].pb(i);
}
rep(i,0,SZ(A)) a[i+N]=A[i];
}
pii solve(int u) {
if (SZ(edge[u])==0) {
if (a[u]==0) return {0,1};
else return {1,0};
}
vector <pii> ans;
for (int v:edge[u]) {
ans.pb(solve(v));
}
vector <int> f;
f.pb(1);
rep(i,0,SZ(ans)) {
f.pb(1ll*f.back()*ans[i].fi%mod);
for (int j = i;j>=0;j--) {
f[j] = 1ll*f[j]*ans[i].se%mod;
if (j>0) inc(f[j],1ll*f[j-1]*ans[i].fi%mod);
}
}
pii ret = {0,0};
rep(i,0,SZ(f)) {
inc(ret.se,1ll*f[i]*(SZ(f)-1-i)%mod);
inc(ret.fi,1ll*f[i]*i%mod);
}
return ret;
}
int count_ways(int L, int R) {
rep(i,L,R+1) a[i]^=1;
return solve(0).fi;
}
