Submission #1439851

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Source Code Expand

#include <iostream>
#include <map>
#include <vector>
#include <cstring>
#include <utility>
#include <algorithm>
#include <cstdio>
#include <queue>
#include <string>
#include <stack>
#include <set>
#include <deque>
#define mp make_pair
using namespace std;
int n,a[100005],maxi,in[100005],f[100005];
vector <int> ve[100005],hw,v,inv[100005];
void dfs(int p,int d){
	if (p==1){
		v.push_back(d);
		return;
	}
	f[p]=d;
	int pv=0;
	for (int i=0;i<inv[a[p]].size();i++){
		if (inv[a[p]][i]>=f[p]){
			pv=i;
			break;
		}
	}
	inv[a[p]].push_back(f[p]); 
	dfs(a[p],d+pv+1);
}
int main(){
	ios::sync_with_stdio(false);
	cin>>n;
	for (int i=2;i<=n;i++){
		cin>>a[i];
		in[a[i]]++;
	}
	for (int i=1;i<=n;i++){
		if (in[i]==0) hw.push_back(i); 
	}
	for (int i=0;i<hw.size();i++){
		dfs(hw[i],0);
	}
	sort(v.begin(),v.end());
	for (int i=0;i<v.size();i++){
		maxi=max(maxi,int(v[i]+(v.size()-i-1)));
	}
	cout<<maxi;
	return 0;
}

Submission Info

Judge Result