diff --git a/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/CMakeLists.txt b/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/CMakeLists.txt
new file mode 100644
index 00000000..bee29d53
--- /dev/null
+++ b/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/CMakeLists.txt
@@ -0,0 +1,6 @@
+cmake_minimum_required(VERSION 3.14)
+project(D)
+
+set(CMAKE_CXX_STANDARD 14)
+
+add_executable(D main2.cpp)
\ No newline at end of file
diff --git a/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/main.cpp b/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/main.cpp
new file mode 100644
index 00000000..6282d848
--- /dev/null
+++ b/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/main.cpp
@@ -0,0 +1,47 @@
+/// Source : https://leetcode.com/problems/maximum-nesting-depth-of-two-valid-parentheses-strings/
+/// Author : liuyubobobo
+/// Time   : 2019-07-06
+
+#include <iostream>
+#include <vector>
+#include <cassert>
+
+using namespace std;
+
+
+/// Halve max depth
+/// Time Complexity: O(2n)
+/// Space Complexity: O(1)
+class Solution {
+public:
+    vector<int> maxDepthAfterSplit(string s) {
+
+        int bound = get_depth(s) / 2;
+
+        vector<int> res(s.size(), 0);
+        int stack = 0;
+        for(int i = 0; i < s.size(); i ++){
+            if(s[i] == '(') stack ++, res[i] = (stack > bound);
+            else res[i] = (stack > bound), stack --;
+
+        }
+        return res;
+    }
+
+private:
+    int get_depth(const string& s){
+
+        int res = 0, stack = 0;
+        for(char c: s)
+            if(c == '(') stack ++, res = max(res, stack);
+            else stack --;
+        assert(!stack);
+        return res;
+    }
+};
+
+
+int main() {
+
+    return 0;
+}
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diff --git a/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/main2.cpp b/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/main2.cpp
new file mode 100644
index 00000000..51d3afe1
--- /dev/null
+++ b/1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/main2.cpp
@@ -0,0 +1,33 @@
+/// Source : https://leetcode.com/problems/maximum-nesting-depth-of-two-valid-parentheses-strings/
+/// Author : liuyubobobo
+/// Time   : 2019-07-07
+
+#include <iostream>
+#include <vector>
+#include <cassert>
+
+using namespace std;
+
+
+/// Alternatively Assign 0 and 1
+/// Time Complexity: O(n)
+/// Space Complexity: O(1)
+class Solution {
+public:
+    vector<int> maxDepthAfterSplit(string s) {
+
+        vector<int> res(s.size(), 0);
+
+        int stack = 0;
+        for(int i = 0; i < s.size(); i ++)
+            if(s[i] == '(') stack ++, res[i] = stack % 2;
+            else res[i] = stack % 2, stack --;
+        return res;
+    }
+};
+
+
+int main() {
+
+    return 0;
+}
\ No newline at end of file
diff --git a/readme.md b/readme.md
index 12bec6cc..9e8e0219 100644
--- a/readme.md
+++ b/readme.md
@@ -753,4 +753,5 @@ email: [liuyubobobo@gmail.com](mailto:liuyubobobo@gmail.com)
 | 1108 | [Defanging an IP Address](https://leetcode.com/problems/defanging-an-ip-address/) | [无] | [C++](1108-Defanging-an-IP-Address/cpp-1108/) | | |
 | 1109 | [Corporate Flight Bookings](https://leetcode.com/problems/corporate-flight-bookings/) | [无] | [C++](1109-Corporate-Flight-Bookings/cpp-1009/) | | |
 | 1110 | [Delete Nodes And Return Forest](https://leetcode.com/problems/delete-nodes-and-return-forest/) | [无] | [C++](1110-Delete-Nodes-And-Return-Forest/cpp-1110/) | | |
+| 1111 | [Maximum Nesting Depth of Two Valid Parentheses Strings](https://leetcode.com/problems/maximum-nesting-depth-of-two-valid-parentheses-strings/) | [无] | [C++](1111-Maximum-Nesting-Depth-of-Two-Valid-Parentheses-Strings/cpp-1111/) | | |
 | | | | | | |
\ No newline at end of file