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@@ -0,0 +1,55 @@
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+/**
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+ * Definition for a binary tree node.
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+ * type TreeNode struct {
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+ * Val int
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+ * Left *TreeNode
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+ * Right *TreeNode
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+ * }
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+ */
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+func largestValues(root *TreeNode) (res []int) {
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+ preorder(root, 0, &res) // DFS
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+ return
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+}
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+
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+func preorder(root *TreeNode, depth int, res *[]int) {
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+ if root == nil {
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+ return
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+ }
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+ if depth == len(*res) {
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+ *res = append(*res, root.Val)
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+ } else if (*res)[depth] < root.Val {
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+ (*res)[depth] = root.Val
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+ }
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+ preorder(root.Left, depth+1, res)
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+ preorder(root.Right, depth+1, res)
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+}
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+
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+func largestValuesBFS(root *TreeNode) (res []int) {
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+ if root == nil {
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+ return
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+ }
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+ queue := make([]*TreeNode, 0)
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+ queue = append(queue, root)
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+ size := 1
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+ for size != 0 {
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+ max, l := queue[0].Val, size
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+ for i := 0; i < l; i++ {
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+ node := queue[0]
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+ queue = queue[1:]
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+ size--
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+ if max < node.Val {
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+ max = node.Val
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+ }
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+ if node.Left != nil {
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+ queue = append(queue, node.Left)
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+ size++
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+ }
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+ if node.Right != nil {
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+ queue = append(queue, node.Right)
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+ size++
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+ }
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+ }
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+ res = append(res, max)
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+ }
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+ return
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+}
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