Solution 1. Two Sum

Author: vkazakevich

README.md

@@ -10,4 +10,5 @@ The repository contains the best versions of my solutions to [LeetCode](https://
 | # | Title | Solution | Time | Space |
 |---| ----- | -------- | ---- | ----- |
 |217|[Contains Duplicate](https://leetcode.com/problems/contains-duplicate/)|[Python](./Solutions/217-contains-duplicate.py)|O(n)|O(n)|
-|53|[Maximum Subarray](https://leetcode.com/problems/maximum-subarray/)|[Python](./Solutions/53-maximum-subarray.py)|O(n)|O(1)|
+|53|[Maximum Subarray](https://leetcode.com/problems/maximum-subarray/)|[Python](./Solutions/53-maximum-subarray.py)|O(n)|O(1)|
+|1|[Two Sum](https://leetcode.com/problems/two-sum/)|[Python](./Solutions/1-two-sum.py)|O(n^2)|O(1)|

Solutions/1-two-sum.py

@@ -0,0 +1,41 @@
+'''
+Given an array of integers nums and an integer target, return indices of 
+the two numbers such that they add up to target.
+
+You may assume that each input would have exactly one solution, 
+and you may not use the same element twice.
+
+You can return the answer in any order.
+
+Example 1:
+Input: nums = [2,7,11,15], target = 9
+Output: [0,1]
+Explanation: Because nums[0] + nums[1] == 9, we return [0, 1].
+
+Example 2:
+Input: nums = [3,2,4], target = 6
+Output: [1,2]
+
+Example 3:
+Input: nums = [3,3], target = 6
+Output: [0,1]
+'''
+
+from typing import List
+
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+        length = len(nums)
+
+        for i in range(length - 1):
+            if nums[i] + nums[i + 1] == target:
+                return [i, i + 1]
+        
+        for i in range(length - 1):
+            for j in range(i + 1, length):
+                if nums[i] + nums[j] == target:
+                    return [i, j]
+
+# Result
+s = Solution()
+print(s.twoSum([3,2,3], 6))

Solutions/217-contains-duplicate.py

@@ -16,7 +16,6 @@
 '''
 
 from typing import List
-
 class Solution:
     def containsDuplicate(self, nums: List[int]) -> bool:
         duplicates = {}

Solutions/53-maximum-subarray.py

@@ -19,8 +19,6 @@
 '''
 
 from typing import List
-
-
 class Solution:
     def maxSubArray(self, nums: List[int]) -> int:
         currentSum = 0
@@ -38,4 +36,4 @@ def maxSubArray(self, nums: List[int]) -> int:
 
 # Result
 s = Solution()
-print(s.containsDuplicate([-2, 1, -3, 4, -1, 2, 1, -5, 4]))  # 6
+print(s.maxSubArray([-2, 1, -3, 4, -1, 2, 1, -5, 4]))  # 6