Submission #1073733

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Source Code Expand

#include <bits/stdc++.h>

using namespace std;

int main() {
	int n;
	cin >> n;

	vector<int> Beaten(n);
	vector<int> Beats(n);
	vector<int> H(n);

	for(int i = 1; i < n; ++i) {
		cin >> Beaten[i];
		Beaten[i] -= 1;
		Beats[Beaten[i]] += 1;
	}

	cerr << "OK" << endl;

	queue<int> Q;
	for(int i = 0; i < n; ++i) {
		if(Beats[i] == 0) {
			Q.push(i);
		}
	}

	for(int i = 1; i < n; ++i) {
		int top = Q.front();
		Q.pop();

		int par = Beaten[top];
		H[par] = max(H[par], H[top] + 1);
		if(--Beats[par] == 0)
			Q.push(par);
	}

	cout << H[0] << endl;

	return 0;
}

Submission Info

Judge Result