From 76b63ad81ebf9b3185d60ce36f380e52416eae25 Mon Sep 17 00:00:00 2001 From: junyoungKim Date: Sat, 6 Dec 2025 02:07:29 +0900 Subject: [PATCH 1/4] Merge Two Sorted Lists solution --- merge-two-sorted-lists/kimjunyoung90.java | 25 +++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 merge-two-sorted-lists/kimjunyoung90.java diff --git a/merge-two-sorted-lists/kimjunyoung90.java b/merge-two-sorted-lists/kimjunyoung90.java new file mode 100644 index 0000000000..4016b9835d --- /dev/null +++ b/merge-two-sorted-lists/kimjunyoung90.java @@ -0,0 +1,25 @@ +public class Solution { + public ListNode mergeTwoLists(ListNode list1, ListNode list2) { + //1. null 체크 + if(list1 == null || list2 == null) { + return list1 != null ? list1 : list2; + } + //1. 값 비교 + if(list1.val < list2.val) { + //다음 Node 비교 + list1.next = mergeTwoLists(list1.next, list2); + return list1; + } else { + list2.next = mergeTwoLists(list1, list2.next); + return list2; + } + } +} + +class ListNode { + int val; + ListNode next; + ListNode() {} + ListNode(int val) { this.val = val; } + ListNode(int val, ListNode next) { this.val = val; this.next = next; } +} From 934a0afa587915690188d9b9788ae6be5bcd5aab Mon Sep 17 00:00:00 2001 From: junyoungKim Date: Sat, 6 Dec 2025 02:24:33 +0900 Subject: [PATCH 2/4] Maximum Depth of Binary Tree solution --- .../kimjunyoung90.java | 25 +++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 maximum-depth-of-binary-tree/kimjunyoung90.java diff --git a/maximum-depth-of-binary-tree/kimjunyoung90.java b/maximum-depth-of-binary-tree/kimjunyoung90.java new file mode 100644 index 0000000000..56c0cf2399 --- /dev/null +++ b/maximum-depth-of-binary-tree/kimjunyoung90.java @@ -0,0 +1,25 @@ +public class Solution { + public int maxDepth(TreeNode root) { + if (root == null) return 0; + return 1 + Math.max(maxDepth(root.left), maxDepth(root.right)); + } +} + +class TreeNode { + int val; + TreeNode left; + TreeNode right; + + TreeNode() { + } + + TreeNode(int val) { + this.val = val; + } + + TreeNode(int val, TreeNode left, TreeNode right) { + this.val = val; + this.left = left; + this.right = right; + } +} \ No newline at end of file From 5f7a92b2aeb829e64921abf226ed34a74c2c3c46 Mon Sep 17 00:00:00 2001 From: junyoungKim Date: Sat, 6 Dec 2025 18:00:26 +0900 Subject: [PATCH 3/4] Maximum Depth of Binary Tree solution --- .../kimjunyoung90.java | 19 ------------------- 1 file changed, 19 deletions(-) diff --git a/maximum-depth-of-binary-tree/kimjunyoung90.java b/maximum-depth-of-binary-tree/kimjunyoung90.java index 56c0cf2399..c1d851676c 100644 --- a/maximum-depth-of-binary-tree/kimjunyoung90.java +++ b/maximum-depth-of-binary-tree/kimjunyoung90.java @@ -4,22 +4,3 @@ public int maxDepth(TreeNode root) { return 1 + Math.max(maxDepth(root.left), maxDepth(root.right)); } } - -class TreeNode { - int val; - TreeNode left; - TreeNode right; - - TreeNode() { - } - - TreeNode(int val) { - this.val = val; - } - - TreeNode(int val, TreeNode left, TreeNode right) { - this.val = val; - this.left = left; - this.right = right; - } -} \ No newline at end of file From b7ad44ac6993847932ec1e8254efe5584359d15b Mon Sep 17 00:00:00 2001 From: junyoungKim Date: Sat, 6 Dec 2025 18:00:45 +0900 Subject: [PATCH 4/4] Maximum Depth of Binary Tree solution --- merge-two-sorted-lists/kimjunyoung90.java | 8 -------- 1 file changed, 8 deletions(-) diff --git a/merge-two-sorted-lists/kimjunyoung90.java b/merge-two-sorted-lists/kimjunyoung90.java index 4016b9835d..0e40239a7b 100644 --- a/merge-two-sorted-lists/kimjunyoung90.java +++ b/merge-two-sorted-lists/kimjunyoung90.java @@ -15,11 +15,3 @@ public ListNode mergeTwoLists(ListNode list1, ListNode list2) { } } } - -class ListNode { - int val; - ListNode next; - ListNode() {} - ListNode(int val) { this.val = val; } - ListNode(int val, ListNode next) { this.val = val; this.next = next; } -}