From 257eded1cc1575854e339dfadaa694bad1087f72 Mon Sep 17 00:00:00 2001
From: Eat-Swap <root@eatswap.org>
Date: Sun, 8 May 2022 16:25:37 +0800
Subject: [PATCH] add: 220508-CN [cpp]

---
 cpp/2205/220508-CN.cpp  | 24 ++++++++++++++++++++++++
 cpp/2205/CMakeLists.txt |  2 +-
 2 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 cpp/2205/220508-CN.cpp

diff --git a/cpp/2205/220508-CN.cpp b/cpp/2205/220508-CN.cpp
new file mode 100644
index 0000000..e084ef0
--- /dev/null
+++ b/cpp/2205/220508-CN.cpp
@@ -0,0 +1,24 @@
+#include <vector>
+#include <bitset>
+
+/**
+ * 442. Find All Duplicates in an Array
+ * Given an integer array nums of length n where all the integers of nums are in the range [1, n] and each integer appears once or twice, return an array of all the integers that appears twice.
+ * You must write an algorithm that runs in O(n) time and uses only constant extra space.
+ */
+
+class Solution {
+public:
+	static std::vector<int> findDuplicates(const std::vector<int>& nums) {
+		std::bitset<100001> s;
+		std::vector<int> v;
+		v.reserve(nums.size());
+		for (auto i : nums) {
+			if (s.test(i))
+				v.push_back(i);
+			else
+				s.set(i);
+		}
+		return v;
+	}
+};
diff --git a/cpp/2205/CMakeLists.txt b/cpp/2205/CMakeLists.txt
index 6eb00bb..6be1653 100644
--- a/cpp/2205/CMakeLists.txt
+++ b/cpp/2205/CMakeLists.txt
@@ -3,4 +3,4 @@ PROJECT(2205)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2205 220508.cpp)
+ADD_EXECUTABLE(2205 220508-CN.cpp)