init

dynamic planning/*22.cpp

@@ -0,0 +1,23 @@
+#include <string>
+#include <vector>
+
+using namespace std;
+
+class Solution {
+    public:
+        vector<string> generateParenthesis(int n) {
+            vector<string> v;
+            dfs(v, "", n, n);
+            return v;
+        }
+        void dfs(vector<string> &v, string s, int lc, int rc){
+            if(lc == 0 && rc == 0){
+                v.push_back(s);
+                return;
+            }
+            if(lc != 0) dfs(v, s + '(', lc - 1, rc);
+            if(rc != 0 && rc - 1 >= lc){
+                dfs(v, s + ')', lc, rc - 1);
+            }
+        }
+    };