backtracking-2

PalindromPartitioning.cs

@@ -0,0 +1,43 @@
+public class Solution {
+    public IList<IList<string>> Partition(string s) {
+        List<IList<string>> result = new ();
+        helper(s,0,new List<string>(),result);
+        return result;
+    }
+
+    public void helper(string s,int pivot,List<string> path, List<IList<string>> result)
+    {
+        if(s.Length==pivot)
+            {
+                result.Add(new List<string>(path));
+                return;
+            }
+        for(int i=pivot;i<s.Length;i++)
+        {
+            string curstr = s.Substring(pivot,i-pivot + 1);
+            if(IsPalindrome(curstr))
+            {
+                path.Add(curstr);
+                helper(s,i+1,path,result);
+                path.RemoveAt(path.Count - 1);
+            }
+        }
+    }
+    public bool IsPalindrome(string s)
+    {
+        int i = 0 ;int j = s.Length - 1;
+        while(i <= j)
+        {
+            if(s[i++]!=s[j--])
+            {
+                return false;
+            }
+        }
+        return true;
+    }
+}
+// Time Complexity:
+// O(2^n * n) -> For n length string, exponential partitions × (palindrome checks + creating substrings)
+
+// Space Complexity:
+// O(n^2) (substring creation and recursion stack)

Subsets.cs

@@ -0,0 +1,21 @@
+public class Solution
+{
+    public IList<IList<int>> Subsets(int[] nums)
+    {
+        List<IList<int>> result = new();
+        result.Add(new List<int>());
+        for (int i = 0; i < nums.Length; i++)
+        {
+            int size = result.Count;
+            for (int j = 0; j < size; j++)
+            {
+                List<int> subset = new List<int>(result[j]);
+                subset.Add(nums[i]);
+                result.Add(subset);
+            }
+        }
+
+        return result;
+    }
+}
+//Time and space - O(n * 2^n)