diff --git a/Week_02/id_103/.idea/id_103.iml b/Week_02/id_103/.idea/id_103.iml
new file mode 100644
index 00000000..c956989b
--- /dev/null
+++ b/Week_02/id_103/.idea/id_103.iml
@@ -0,0 +1,8 @@
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\ No newline at end of file
diff --git a/Week_02/id_103/.idea/misc.xml b/Week_02/id_103/.idea/misc.xml
new file mode 100644
index 00000000..28a804d8
--- /dev/null
+++ b/Week_02/id_103/.idea/misc.xml
@@ -0,0 +1,6 @@
+
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\ No newline at end of file
diff --git a/Week_02/id_103/.idea/modules.xml b/Week_02/id_103/.idea/modules.xml
new file mode 100644
index 00000000..9bdd8e3d
--- /dev/null
+++ b/Week_02/id_103/.idea/modules.xml
@@ -0,0 +1,8 @@
+
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\ No newline at end of file
diff --git a/Week_02/id_103/.idea/vcs.xml b/Week_02/id_103/.idea/vcs.xml
new file mode 100644
index 00000000..b2bdec2d
--- /dev/null
+++ b/Week_02/id_103/.idea/vcs.xml
@@ -0,0 +1,6 @@
+
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+
\ No newline at end of file
diff --git a/Week_02/id_103/.idea/workspace.xml b/Week_02/id_103/.idea/workspace.xml
new file mode 100644
index 00000000..6bb83417
--- /dev/null
+++ b/Week_02/id_103/.idea/workspace.xml
@@ -0,0 +1,213 @@
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+ NodeVal
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+ file://$PROJECT_DIR$/P373.go
+ 57
+
+
+
+ file://$PROJECT_DIR$/P429.go
+ 40
+
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\ No newline at end of file
diff --git a/Week_03/id_103/LeetCode_104_103.go b/Week_03/id_103/LeetCode_104_103.go
new file mode 100644
index 00000000..8fe30ebe
--- /dev/null
+++ b/Week_03/id_103/LeetCode_104_103.go
@@ -0,0 +1,25 @@
+package main
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ * Val int
+ * Left *TreeNode
+ * Right *TreeNode
+ * }
+ */
+func maxDepth(root *TreeNode) int {
+ if root == nil {
+ return 0
+ }
+ left := maxDepth(root.Left) + 1
+ right := maxDepth(root.Right) + 1
+ if left > right {
+ return left
+ }
+ return right
+}
+
+func main() {
+ vr := TreeNode{}
+ maxDepth(&vr)
+}
\ No newline at end of file
diff --git a/Week_03/id_103/LeetCode_373_103.go b/Week_03/id_103/LeetCode_373_103.go
new file mode 100644
index 00000000..072294fc
--- /dev/null
+++ b/Week_03/id_103/LeetCode_373_103.go
@@ -0,0 +1,62 @@
+package main
+
+import (
+ "container/heap"
+ "fmt"
+)
+
+type minHeap [][]int
+
+func (m minHeap) Len() int {
+ return len(m)
+}
+
+func (m minHeap) Less(i, j int) bool {
+ v1 := m[i][0] + m[i][1]
+ v2 := m[j][0] + m[j][1]
+ return v1 > v2
+}
+
+func (m minHeap) Swap(i, j int) {
+ m[i],m[j] = m[j], m[i]
+}
+
+func (m *minHeap) Push(x interface{}) {
+ *m = append(*m, x.([]int))
+}
+
+func (m *minHeap) Pop() interface{} {
+ old := *m
+ n := len(old)
+ x := old[n-1]
+ *m = old[0 : n-1]
+ return x
+}
+
+func kSmallestPairs(nums1 []int, nums2 []int, k int) [][]int {
+ v := &minHeap{}
+ heap.Init(v)
+ for _,v1 := range nums1 {
+ for _,v2 := range nums2 {
+ if v.Len() < k {// 这里不能都添加完在移除，因为在pop哪里，移除方法并不是移除最大的，而是最后一个，如果保证堆内的数量，则可以保证，移除的一定是最大的。
+ heap.Push(v,[]int{v1,v2})
+ }else {
+ heap.Push(v,[]int{v1,v2})
+ heap.Pop(v)
+ }
+ }
+ }
+ fmt.Println(v)
+ for v.Len() > k {
+ v.Pop()
+ }
+ fmt.Println(v)
+ return *v
+}
+
+func main() {
+ num1 := []int{1,2,4,5,6}
+ num2 := []int{3,5,7,9}
+ kSmallestPairs(num1,num2,3)
+}
+
diff --git a/Week_03/id_103/LeetCode_429_103.go b/Week_03/id_103/LeetCode_429_103.go
new file mode 100644
index 00000000..35e5d97b
--- /dev/null
+++ b/Week_03/id_103/LeetCode_429_103.go
@@ -0,0 +1,42 @@
+package main
+
+import "fmt"
+
+type NodeVal struct {
+ Val int
+ Children []*NodeVal
+}
+
+func LevelOrder(root *NodeVal) [][]int {
+ res := make([][]int,0)
+ if root == nil {
+ return res
+ }
+ Add(root,0, &res)
+ return res
+}
+
+func Add(node *NodeVal, index int, res *[][]int) {
+ if len(*res) <= index{
+ *res = append(*res, []int{})
+ }
+ childrens := *res
+ childrens[index] = append(childrens[index], node.Val)
+ if node.Children != nil{
+ for i, _ := range node.Children {
+ Add(node.Children[i],index+1,res)
+ }
+ }
+}
+
+func main() {
+ node1 := NodeVal{1,make([]*NodeVal,0)}
+ node2 := NodeVal{2,make([]*NodeVal,0)}
+ node3 := NodeVal{3,make([]*NodeVal,0)}
+ node4 := NodeVal{4,make([]*NodeVal,0)}
+ node5 := NodeVal{5,make([]*NodeVal,0)}
+ node6 := NodeVal{6,make([]*NodeVal,0)}
+ node1.Children = append(append(append(node1.Children, &node3), &node2), &node4)
+ node3.Children = append(append(node3.Children, &node5), &node6)
+ fmt.Println(LevelOrder(&node1))
+}
\ No newline at end of file
diff --git a/Week_03/id_103/LeetCode_703_103.go b/Week_03/id_103/LeetCode_703_103.go
new file mode 100644
index 00000000..09fc968c
--- /dev/null
+++ b/Week_03/id_103/LeetCode_703_103.go
@@ -0,0 +1,55 @@
+package main
+
+import "container/heap"
+
+// copied from golang doc
+// mininum setup of integer min heap
+type IntHeap []int
+
+func (h IntHeap) Len() int { return len(h) }
+func (h IntHeap) Less(i, j int) bool { return h[i] < h[j] }
+func (h IntHeap) Swap(i, j int) { h[i], h[j] = h[j], h[i] }
+
+func (h *IntHeap) Push(x interface{}) {
+ // Push and Pop use pointer receivers because they modify the slice's length,
+ // not just its contents.
+ *h = append(*h, x.(int))
+}
+
+func (h *IntHeap) Pop() interface{} {
+ old := *h
+ n := len(old)
+ x := old[n-1]
+ *h = old[0 : n-1]
+ return x
+}
+
+// real thing starts here
+type KthLargest struct {
+ Nums *IntHeap
+ K int
+}
+
+func Constructor(k int, nums []int) KthLargest {
+ h := &IntHeap{}
+ heap.Init(h)
+ // push all elements to the heap
+ for i := 0; i < len(nums); i++ {
+ heap.Push(h, nums[i])
+ }
+ // remove the smaller elements from the heap such that only the k largest elements are in the heap
+ for len(*h) > k {
+ heap.Pop(h)
+ }
+ return KthLargest{h, k}
+}
+
+func (this *KthLargest) Add(val int) int {
+ if len(*this.Nums) < this.K {
+ heap.Push(this.Nums, val)
+ } else if val > (*this.Nums)[0] {
+ heap.Push(this.Nums, val)
+ heap.Pop(this.Nums)
+ }
+ return (*this.Nums)[0]
+}
\ No newline at end of file
diff --git a/Week_03/id_103/NOTE.md b/Week_03/id_103/NOTE.md
index c684e62f..ed3a25b2 100644
--- a/Week_03/id_103/NOTE.md
+++ b/Week_03/id_103/NOTE.md
@@ -1 +1,9 @@
-# 学习笔记
\ No newline at end of file
+# 学习笔记
+
+[104 - 树最大深度](https://www.jianshu.com/p/e408e356f776)
+
+[373 - 查找最小的n个值](https://www.jianshu.com/p/6159b20721e1)
+
+[429 - 按照树的层级整理数据](https://www.jianshu.com/p/f2bc04222138)
+
+[703 - k个数，最大的值](https://www.jianshu.com/p/26b22e0bd8ac)
\ No newline at end of file
diff --git a/Week_03/id_103/TreeNode.go b/Week_03/id_103/TreeNode.go
new file mode 100644
index 00000000..e635bd4f
--- /dev/null
+++ b/Week_03/id_103/TreeNode.go
@@ -0,0 +1,11 @@
+package main
+
+
+type TreeNode struct {
+ Val int
+ Left *TreeNode
+ Right *TreeNode
+}
+
+
+
diff --git a/Week_03/id_103/main.go b/Week_03/id_103/main.go
new file mode 100644
index 00000000..79058077
--- /dev/null
+++ b/Week_03/id_103/main.go
@@ -0,0 +1,5 @@
+package main
+
+func main() {
+
+}