From 2080c40b204d8adcb70dd1c25a7b2bbba63c8b9c Mon Sep 17 00:00:00 2001
From: Lam Haoyin <root@eatswap.org>
Date: Sun, 13 Feb 2022 15:47:25 +0800
Subject: [PATCH] add: 220213-CN

---
 2202/220213.cpp     | 35 +++++++++++++++++++++++++++++++++++
 2202/CMakeLists.txt |  2 +-
 2 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 2202/220213.cpp

diff --git a/2202/220213.cpp b/2202/220213.cpp
new file mode 100644
index 0000000..02339f8
--- /dev/null
+++ b/2202/220213.cpp
@@ -0,0 +1,35 @@
+#include <vector>
+#include <cstdio>
+
+/**
+ * 78. Subsets
+ * Given an integer array nums of unique elements, return all possible subsets (the power set).
+ * The solution set must not contain duplicate subsets. Return the solution in any order.
+ */
+
+class Solution {
+public:
+	static std::vector<std::vector<int>> subsets(const std::vector<int>& nums) {
+		int s = (1 << nums.size()), n = nums.size();
+		std::vector<std::vector<int>> ret(s);
+		for (int i = 0; i < s; ++i) {
+			std::vector<int>& t = ret[i];
+			t.reserve(n);
+			for (int j = 0; j < n; ++j)
+				if (i & (1 << j))
+					t.push_back(nums[j]);
+		}
+		return ret;
+	}
+};
+
+int main() {
+	const auto ret = Solution::subsets({1,2,3});
+	for (const auto& i : ret) {
+		for (const auto& j : i) {
+			std::printf("%d ", j);
+		}
+		std::printf("\n");
+	}
+	return 0;
+}
diff --git a/2202/CMakeLists.txt b/2202/CMakeLists.txt
index c9cf3eb..beda610 100644
--- a/2202/CMakeLists.txt
+++ b/2202/CMakeLists.txt
@@ -3,4 +3,4 @@ PROJECT(2202)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2202 220213-CN.cpp)
+ADD_EXECUTABLE(2202 220213.cpp)