From 2c0614e7df4da516401b18fb3c671ea8c88786ee Mon Sep 17 00:00:00 2001
From: Sangeeth Sudheer <sangeeth96@users.noreply.github.com>
Date: Mon, 4 Apr 2022 22:31:58 +0530
Subject: [PATCH] feat(528-swapping-nodes-in-a-ll): add py3 solution

---
 .../README.md                                 | 23 +++++++++++++++++++
 .../python3/solution.py                       |  0
 .../python3/using_dict.py                     | 17 ++++++++++++++
 3 files changed, 40 insertions(+)
 create mode 100644 0528_swapping-nodes-in-a-linked-list/README.md
 create mode 100644 0528_swapping-nodes-in-a-linked-list/python3/solution.py
 create mode 100644 0528_swapping-nodes-in-a-linked-list/python3/using_dict.py

diff --git a/0528_swapping-nodes-in-a-linked-list/README.md b/0528_swapping-nodes-in-a-linked-list/README.md
new file mode 100644
index 0000000..aa0bfde
--- /dev/null
+++ b/0528_swapping-nodes-in-a-linked-list/README.md
@@ -0,0 +1,23 @@
+You are given the `head` of a linked list, and an integer `k`.
+
+Return _the head of the linked list after **swapping** the values of the_ `kth` _node from the beginning and the_ `kth` _node from the end (the list is **1-indexed**)._
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2020/09/21/linked1.jpg)
+
+    Input: head = [1,2,3,4,5], k = 2
+    Output: [1,4,3,2,5]
+    
+
+**Example 2:**
+
+    Input: head = [7,9,6,6,7,8,3,0,9,5], k = 5
+    Output: [7,9,6,6,8,7,3,0,9,5]
+    
+
+**Constraints:**
+
+*   The number of nodes in the list is `n`.
+*   `1 <= k <= n <= 105`
+*   `0 <= Node.val <= 100`
\ No newline at end of file
diff --git a/0528_swapping-nodes-in-a-linked-list/python3/solution.py b/0528_swapping-nodes-in-a-linked-list/python3/solution.py
new file mode 100644
index 0000000..e69de29
diff --git a/0528_swapping-nodes-in-a-linked-list/python3/using_dict.py b/0528_swapping-nodes-in-a-linked-list/python3/using_dict.py
new file mode 100644
index 0000000..7e78925
--- /dev/null
+++ b/0528_swapping-nodes-in-a-linked-list/python3/using_dict.py
@@ -0,0 +1,17 @@
+# NOTE: Not the best approach, since we use O(N) space
+# Time: O(N)
+class Solution:
+    def swapNodes(self, head: Optional[ListNode], k: int) -> Optional[ListNode]:
+        # Figure out length of LL and cache nodes by the index
+        length = 0
+        cache = {}
+        
+        ptr = head
+        while ptr != None:
+            cache[length] = ptr
+            length += 1
+            ptr = ptr.next
+        
+        cache[k - 1].val, cache[length - k].val = cache[length - k].val, cache[k - 1].val
+        
+        return head