From 6450ef0347db756ab6b4b183a9883f007d443dbe Mon Sep 17 00:00:00 2001
From: Sangeeth Sudheer <sangeeth96@users.noreply.github.com>
Date: Tue, 26 Apr 2022 02:26:40 +0530
Subject: [PATCH] single-number py3

---
 0136_single-number/README.md           | 29 ++++++++++++++++++++++++++
 0136_single-number/python3/solution.py |  5 +++++
 2 files changed, 34 insertions(+)
 create mode 100644 0136_single-number/README.md
 create mode 100644 0136_single-number/python3/solution.py

diff --git a/0136_single-number/README.md b/0136_single-number/README.md
new file mode 100644
index 0000000..822902f
--- /dev/null
+++ b/0136_single-number/README.md
@@ -0,0 +1,29 @@
+Given a **non-empty** array of integers `nums`, every element appears _twice_ except for one. Find that single one.
+
+You must implement a solution with a linear runtime complexity and use only constant extra space.
+
+**Example 1:**
+
+    Input: nums = [2,2,1]
+    Output: 1
+    
+
+**Example 2:**
+
+    Input: nums = [4,1,2,1,2]
+    Output: 4
+    
+
+**Example 3:**
+
+    Input: nums = [1]
+    Output: 1
+    
+
+**Constraints:**
+
+*   `1 <= nums.length <= 3 * 104`
+*   `-3 * 104 <= nums[i] <= 3 * 104`
+*   Each element in the array appears twice except for one element which appears only once.
+
+https://leetcode.com/problems/single-number/
\ No newline at end of file
diff --git a/0136_single-number/python3/solution.py b/0136_single-number/python3/solution.py
new file mode 100644
index 0000000..c7dd58f
--- /dev/null
+++ b/0136_single-number/python3/solution.py
@@ -0,0 +1,5 @@
+from functools import reduce
+
+class Solution:
+    def singleNumber(self, nums: List[int]) -> int:
+        return reduce(lambda r, a: r ^ a, nums)