Codeforces Round #453 (Div. 2) B

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#include<iostream>#include<algorithm>#include<iomanip>#include<cstdio>#include<cstdlib>#include<cstring>#include<string>#include<cmath>#include<set>#include<queue>#include<stack>#include<map>#define PI acos(-1.0)#define in freopen("in.txt", "r", stdin)#define out freopen("out.txt", "w", stdout)#define kuaidian ios::sync_with_stdio(0);using namespace std;typedef long long ll;typedef unsigned long long ull;const int maxn = 1e4 + 7, maxd = 1e8;const ll mod = 1e9 + 7;const int INF = 0x7f7f7f7f;int n, ans = 0, ff = 0;vector<int> vec[maxn];int a[maxn];int b[maxn] = {0};void dfs(int id, int f) {    if(a[id] != f) { ans++; }    for(int i = 0; i < vec[id].size(); ++i) {        dfs(vec[id][i], a[id]);    }}int main() {    kuaidian;    cin >> n;    for(int i = 2; i <= n; ++i) {        int x;        cin >> x;        vec[x].push_back(i);    }    for(int i = 1; i <= n; ++i) {        cin >> a[i];    }    ans = 0;    dfs(1, 0);    cout << ans << endl;    return 0;}