day 29: 22-generate-parentheses, 739-daily-temperatures

22-generate-parentheses/driver.cpp

@@ -0,0 +1,12 @@
+#include "soln.hpp"
+
+int main()
+{
+	int n = 4;
+	Solution soln;
+	vector<string> result = soln.generateParenthesis(n);
+	for (string str : result)
+		cout << str << "\t";
+	cout << endl;
+	return 0;
+}

22-generate-parentheses/soln.cpp

@@ -0,0 +1,24 @@
+#include "soln.hpp"
+
+void Solution::recurseParenthesis(vector<string> &result, string str, int left, int right)
+{
+	// base case
+	if (left == 0 & right == 0)
+	{
+		result.push_back(str);
+		return;
+	}
+	// opening parenthesis can be added, so add
+	if (left > 0)
+		recurseParenthesis(result, str + "(", left - 1, right);
+	// closing parenthesis can be added, so add
+	if (right > left)
+		recurseParenthesis(result, str + ")", left, right - 1);
+}
+
+vector<string> Solution::generateParenthesis(int n)
+{
+	vector<string> result;
+	recurseParenthesis(result, "", n, n);
+	return result;
+}

22-generate-parentheses/soln.hpp

@@ -0,0 +1,8 @@
+#include <bits/stdc++.h>
+using namespace std;
+class Solution
+{
+public:
+    void recurseParenthesis(vector<string>& result, string str, int left, int right);
+    vector<string> generateParenthesis(int n);
+};