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-# algorithms
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+# Arrays
+
++ [Two Sum](#two-sum)
+
+## Two sum
+
+https://leetcode.com/problems/two-sum/
+
+```python
+class Solution(object):
+    def twoSum(self, nums, target):
+        """
+        :type nums: List[int]
+        :type target: int
+        :rtype: List[int]
+        """
+
+        indices = {}
+        for index in range(len(nums)):
+            if target - nums[index] in indices:
+                return [indices[target - nums[index]], index]
+            indices[nums[index]] = index
+
+```
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