Binary Tree Longest Consecutive Sequence

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Problem Description

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Solutions

Solution 1: C# (Best: 136 ms)

Metric	Value
Runtime	136 ms
Memory	32.5 MB
Date	2019-02-18

Solution

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     public int val;
 *     public TreeNode left;
 *     public TreeNode right;
 *     public TreeNode(int x) { val = x; }
 * }
 */
public class Solution {
    public int LongestConsecutive(TreeNode root)
    {
       if(root == null) return 0;
    return helper(root, 0, root.val);
    
}

public int helper(TreeNode root, int count, int val)
{
    if (root == null) { return count;}
    count = root.val-val == 1 ? count+1 : 1;
    int left = helper(root.left, count, root.val);
    int right = helper(root.right, count, root.val);
    return Math.Max(Math.Max(left, right), count);

}



}

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Complexity Analysis

Approach	Time	Space
Solution	To be analyzed	To be analyzed