add: 220614-CN

cpp/2206/220614-CN.cpp

@@ -0,0 +1,31 @@
+#include <vector>
+#include <algorithm>
+
+/**
+ * 498. Diagonal Traverse
+ * Given an m x n matrix mat, return an array of all the elements of the array in a diagonal order.
+ */
+
+class Solution {
+public:
+	static std::vector<int> findDiagonalOrder(const std::vector<std::vector<int>>& mat) {
+		const int m = mat.size(), n = mat.front().size();
+		std::vector<int> ans;
+		ans.reserve(m * n);
+		for (int i = 0; i < m + n; ++i)
+			// if (i & 1) -> from x min to x max (m)
+			// else       -> from y min to y max (n)
+			if (!(i & 1))
+				for (int x = std::min(i, m - 1), y = std::min(n, i - x); y < n && x >= 0; --x, ++y)
+					ans.push_back(mat[x][y]);
+			else
+				for (int y = std::min(i, n - 1), x = std::min(m, i - y); x < m && y >= 0; ++x, --y)
+					ans.push_back(mat[x][y]);
+		return ans;
+	}
+};
+
+int main() {
+	auto ret = Solution::findDiagonalOrder({{1,2,3},{4,5,6},{7,8,9},{10,11,12}});
+	return 0;
+}

cpp/2206/CMakeLists.txt

@@ -3,4 +3,4 @@ PROJECT(2206)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2206 220607.cpp)
+ADD_EXECUTABLE(2206 220614-CN.cpp)