Backtracking-2 Assignment Completed

palindrome_partionining.java

@@ -0,0 +1,32 @@
+
+class Solution {
+    List<List<String>> result;
+    public List<List<String>> partition(String s) {
+        this.result= new ArrayList<>();
+        helper(s,0,new ArrayList<>());
+        return result;
+    }
+    private void helper(String s,int pivot,List<String> path){
+        if(pivot == s.length()){
+            result.add(new ArrayList<>(path));
+            return;
+        }
+
+        for(int i=pivot; i<s.length();i++){
+            String subStr = s.substring(pivot, i+1);
+            if(palindrome(subStr)){
+                path.add(subStr);
+                helper(s,i+1,path);
+                path.remove(path.size()-1);
+            }
+        }
+    }
+    private boolean palindrome(String s){
+        int left =0, right = s.length()-1;
+        while(left<right){
+            if(s.charAt(left)!=s.charAt(right)) return false;
+            left++;right--;
+        }
+        return true;
+    }
+}

subsets.java

@@ -0,0 +1,46 @@
+// 0-1 recursion 
+// time complexity - O(n × 2ⁿ)
+//space complexity - O(n)
+// class Solution {
+//     List<List<Integer>> result;
+//     public List<List<Integer>> subsets(int[] nums) {
+//         this.result = new ArrayList<>();
+//         List<Integer> path = new ArrayList<>();
+//         helper(nums, 0, path);
+//         return result;
+//     }
+//     private void helper(int[] nums, int i,List<Integer> path){
+//         //base
+//         if(i==nums.length)
+//         {
+//             result.add(new ArrayList<>(path));
+//             return;
+//         }
+//         //logic 
+//         //0
+//         helper(nums,i+1,path);
+//         path.add(nums[i]);
+//         helper(nums,i+1,path);
+//         path.remove(path.size()-1);
+//     }
+// }
+
+//Time Complexity: O(n × 2ⁿ) 
+//Space Complexity: O(n)
+class Solution {
+    List<List<Integer>> result;
+    public List<List<Integer>> subsets(int[] nums) {
+        this.result = new ArrayList<>();
+        List<Integer> path = new ArrayList<>();
+        helper(nums,path,0);
+        return result;
+    }
+    private void helper(int[] nums,List<Integer> path,int pivot){
+        result.add(new ArrayList(path));
+        for(int i=pivot;i<nums.length;i++){
+            path.add(nums[i]);
+            helper(nums,path,i+1);
+            path.remove(path.size()-1);
+        }
+    }
+}