872. Leaf-Similar Trees

Easy

Consider all the leaves of a binary tree, from left to right order, the values of those leaves form a leaf value sequence.

For example, in the given tree above, the leaf value sequence is (6, 7, 4, 9, 8).

Two binary trees are considered leaf-similar if their leaf value sequence is the same.

Return true if and only if the two given trees with head nodes root1 and root2 are leaf-similar.

Example 1:

Input: root1 = [3,5,1,6,2,9,8,null,null,7,4], root2 = [3,5,1,6,7,4,2,null,null,null,null,null,null,9,8]
Output:
 true

Example 2:

Input: root1 = [1,2,3], root2 = [1,3,2]
Output:
 false

Constraints:

• The number of nodes in each tree will be in the range [1, 200].

• Both of the given trees will have values in the range [0, 200].

解題

Runtime: 0 ms, faster than 100.00%

Memory Usage: 2.6 MB, less than 35.29%

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func leafSimilar(root1 *TreeNode, root2 *TreeNode) bool {
    arr1 := getLeaf(root1)
    arr2 := getLeaf(root2)
    
    return reflect.DeepEqual(arr1, arr2)
}

func getLeaf(root *TreeNode) []int {
    leaves := make([]int, 0)
    
    var recursive func(root *TreeNode) 
    
    recursive = func(root *TreeNode) {
        if root.Left==nil && root.Right==nil {
            leaves = append(leaves, root.Val)
        }
        
        if root.Left!= nil {
            recursive(root.Left)
        }
        
        if root.Right!= nil {
            recursive(root.Right)
        }
    }
    
    recursive(root)
    
    
    return leaves
}