Contains Duplicate

0217.Contains-Duplicate/memo.md

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+# 217. Contains Duplicate
+
+## step1
+setを使って書いた
+
+## step2
+
+## 他の人のコード
+
+https://github.com/huyfififi/coding-challenges/pull/24
+
+https://github.com/ryosuketc/leetcode_grind75/pull/24
+
+https://github.com/syoshida20/leetcode/pull/32
+
+参考にして解法を追加
+
+`len(nums) != len(set(nums))`、ソート後に隣接要素を比較

0217.Contains-Duplicate/step1.py

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+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        seen = set()
+        for n in nums:
+            if n in seen:
+                return True
+            seen.add(n)
+        return False

0217.Contains-Duplicate/step2.py

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+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        return len(nums) != len(set(nums))
+
+
+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        nums.sort()
+        for i in range(len(nums) - 1):
+            if nums[i] == nums[i + 1]:
+                return True
+        return False