feat: 102. Binary Tree Level Order Traversal (#89)

Signed-off-by: ashing <[email protected]>

Author: ronething

leetcode_daily/20240214/102. Binary Tree Level Order Traversal.go

@@ -0,0 +1,32 @@
+package _0240214
+
+import "algorithm/template"
+
+type TreeNode = template.TreeNode
+
+func levelOrder(root *TreeNode) [][]int {
+	res := make([][]int, 0)
+	if root == nil {
+		return res
+	}
+
+	queue := []*TreeNode{root}
+	for len(queue) != 0 {
+		level := make([]int, 0)
+		size := len(queue)
+		for i := 0; i < size; i++ {
+			node := queue[0]
+			queue = queue[1:]
+			level = append(level, node.Val)
+			if node.Left != nil {
+				queue = append(queue, node.Left)
+			}
+			if node.Right != nil {
+				queue = append(queue, node.Right)
+			}
+		}
+		res = append(res, level)
+	}
+
+	return res
+}