From df57a6227524b51fd171e2a9bfbb7c5e818ea57b Mon Sep 17 00:00:00 2001
From: Kaushik Narayan R <rknarayan02@gmail.com>
Date: Fri, 20 Oct 2023 20:58:44 -0700
Subject: [PATCH] some more neetcode

---
 1-two-sum/driver.cpp            | 11 +++++++++++
 1-two-sum/soln.cpp              | 24 ++++++++++++++++++++++++
 1-two-sum/soln.hpp              |  8 ++++++++
 125-valid-palindrome/driver.cpp | 10 ++++++++++
 125-valid-palindrome/soln.cpp   | 32 ++++++++++++++++++++++++++++++++
 125-valid-palindrome/soln.hpp   |  8 ++++++++
 20-valid-parentheses/driver.cpp |  3 ++-
 20-valid-parentheses/soln.cpp   |  3 ++-
 8 files changed, 97 insertions(+), 2 deletions(-)
 create mode 100644 1-two-sum/driver.cpp
 create mode 100644 1-two-sum/soln.cpp
 create mode 100644 1-two-sum/soln.hpp
 create mode 100644 125-valid-palindrome/driver.cpp
 create mode 100644 125-valid-palindrome/soln.cpp
 create mode 100644 125-valid-palindrome/soln.hpp

diff --git a/1-two-sum/driver.cpp b/1-two-sum/driver.cpp
new file mode 100644
index 0000000..f59a29d
--- /dev/null
+++ b/1-two-sum/driver.cpp
@@ -0,0 +1,11 @@
+#include "soln.hpp"
+
+int main()
+{
+	vector<int> nums{2, 7, 11, 15};
+	int target = 9;
+	vector<int> answer{0, 1};
+	Solution soln;
+	cout << "Found two-sum indices correctly? " << soln.test(nums, target, answer) << endl;
+	return 0;
+}
\ No newline at end of file
diff --git a/1-two-sum/soln.cpp b/1-two-sum/soln.cpp
new file mode 100644
index 0000000..d99ad6f
--- /dev/null
+++ b/1-two-sum/soln.cpp
@@ -0,0 +1,24 @@
+#include "soln.hpp"
+
+vector<int> Solution::twoSum(vector<int> &nums, int target)
+{
+	vector<int> result(2);
+	for (int i = 0; i < nums.size(); i++)
+	{
+		for (int j = i + 1; j < nums.size(); j++)
+		{
+			if (nums[i] + nums[j] == target)
+			{
+				result[0] = i;
+				result[1] = j;
+				return result;
+			}
+		}
+	}
+	return result;
+}
+
+bool Solution::test(vector<int> &nums, int target, vector<int> &answer)
+{
+	return twoSum(nums, target) == answer;
+}
\ No newline at end of file
diff --git a/1-two-sum/soln.hpp b/1-two-sum/soln.hpp
new file mode 100644
index 0000000..1573843
--- /dev/null
+++ b/1-two-sum/soln.hpp
@@ -0,0 +1,8 @@
+#include <bits/stdc++.h>
+using namespace std;
+class Solution
+{
+public:
+	vector<int> twoSum(vector<int> &nums, int target);
+	bool test(vector<int> &nums, int target, vector<int> &answer);
+};
\ No newline at end of file
diff --git a/125-valid-palindrome/driver.cpp b/125-valid-palindrome/driver.cpp
new file mode 100644
index 0000000..63eed10
--- /dev/null
+++ b/125-valid-palindrome/driver.cpp
@@ -0,0 +1,10 @@
+#include "soln.hpp"
+
+int main()
+{
+	string s = "A man, a plan, a canal: Panama";
+	bool answer = true;
+	Solution soln;
+	cout << "Checked palindrome correctly? " << soln.test(s, answer) << endl;
+	return 0;
+}
\ No newline at end of file
diff --git a/125-valid-palindrome/soln.cpp b/125-valid-palindrome/soln.cpp
new file mode 100644
index 0000000..524c958
--- /dev/null
+++ b/125-valid-palindrome/soln.cpp
@@ -0,0 +1,32 @@
+#include "soln.hpp"
+
+bool Solution::isPalindrome(string s)
+{
+	int n = s.length();
+	if (n < 2)
+		return true;
+	for (int i = 0; i < n; i++)
+	{
+		if (s[i] >= 'A' && s[i] <= 'Z')
+			s[i] += 32;
+		if ((s[i] < 'a' || s[i] > 'z') &&
+			(s[i] < '0' || s[i] > '9'))
+		{
+			s.erase(s.begin() + i);
+			i--;
+			n--;
+		}
+	}
+	n = s.length();
+	for (int i = 0, j = n - 1; i < n / 2; i++, j--)
+	{
+		if (s[i] != s[n - i - 1])
+			return false;
+	}
+	return true;
+}
+
+bool Solution::test(string s, bool answer)
+{
+	return isPalindrome(s) == answer;
+}
\ No newline at end of file
diff --git a/125-valid-palindrome/soln.hpp b/125-valid-palindrome/soln.hpp
new file mode 100644
index 0000000..643edc1
--- /dev/null
+++ b/125-valid-palindrome/soln.hpp
@@ -0,0 +1,8 @@
+#include <bits/stdc++.h>
+using namespace std;
+class Solution
+{
+public:
+	bool isPalindrome(string s);
+	bool test(string s, bool answer);
+};
\ No newline at end of file
diff --git a/20-valid-parentheses/driver.cpp b/20-valid-parentheses/driver.cpp
index 5df6f25..ac5c7bc 100644
--- a/20-valid-parentheses/driver.cpp
+++ b/20-valid-parentheses/driver.cpp
@@ -1,6 +1,7 @@
 #include "soln.hpp"
 
-int main()	{
+int main()
+{
 	string s = "({[[[]]]})";
 	bool answer = true;
 	Solution soln;
diff --git a/20-valid-parentheses/soln.cpp b/20-valid-parentheses/soln.cpp
index 231c433..d60942f 100644
--- a/20-valid-parentheses/soln.cpp
+++ b/20-valid-parentheses/soln.cpp
@@ -37,6 +37,7 @@ bool Solution::isValid(string s)
 	return bstack.size() == 0;
 }
 
-bool Solution::test(string s, bool answer)	{
+bool Solution::test(string s, bool answer)
+{
 	return isValid(s) == answer;
 }
\ No newline at end of file