generate_parentheses.cpp

Author: jakoo

generate_parentheses.cpp

@@ -0,0 +1,34 @@
+class Solution {
+public:
+    vector<string> generateParenthesis(int n) {
+        vector<string> result;
+        core(n, n, n, string(), result);
+        return result;
+    }
+    
+    void core(int n, int left, int right, string str, vector<string>& result)
+    {
+        if (left == 0)
+        {
+            str.append(right, ')');
+            result.push_back(str);
+            return;
+        }
+        
+        if (left == n)
+        {
+            core(n, left - 1, right, str + '(', result);
+            return;
+        }
+        
+        if (right >= left)
+        {
+            core(n, left - 1, right, str + '(', result);
+        }
+        
+        if (n - right < n - left)
+        {
+            core(n, left, right - 1, str + ')', result);    
+        }
+    }
+};