TopCoder SRM 666 Div1 Easy: WalkOverATree

コード

public class WalkOverATree {

	public int maxNodesVisited(int[] parent, int L) {
		int N = parent.length + 1;

		int[] dist = new int[N];
		int max = 0;
		for (int i = 1; i < N; i++) {
			dist[i] = dist[parent[i - 1]] + 1;
			max = Math.max(max, dist[i]);
		}

		if (L <= max) {
			return L + 1;
		}

		return Math.min(N, (L - max) / 2 + max + 1);
	}
}