add recursion

Recursion/Trying_out_all_Combos_Hard/PalindromePartitioning.java

@@ -0,0 +1,38 @@
+import java.util.*;
+class Solution {
+    boolean isPalindrome(String s, int start, int end) {
+        while (start <= end) {
+            if (s.charAt(start++) != s.charAt(end--))
+                return false;
+        }
+        return true;
+    }
+    public void fun(String s,List<List<String>> ans,List<String> ds,int ind){
+        if(ind==s.length()){
+            ans.add(new ArrayList<>(ds));
+            return;
+        }
+        for(int i=ind;i<s.length();i++){
+            if(isPalindrome(s,ind,i)){
+                ds.add(s.substring(ind,i+1));
+                fun(s,ans,ds,i+1);
+                ds.remove(ds.size()-1);
+            }
+        }
+    }
+    public List<List<String>> partition(String s) {
+        List<List<String>> ans=new ArrayList<>();
+        List<String> ds=new ArrayList<>();
+        fun(s,ans,ds,0);
+        return ans;
+    }
+}
+public class PalindromePartitioning {
+    public static void main(String[] args) {
+        Solution s=new Solution();
+        List<List<String>> ans=s.partition("aab");
+        for(List<String> i:ans){
+            System.out.println(i);
+        }
+    }
+}

Recursion/Trying_out_all_Combos_Hard/RateInmaze.java

@@ -0,0 +1,58 @@
+import java.util.ArrayList;
+import java.util.List;
+
+class Choice {
+    char dName;
+    int dx, dy;
+
+    Choice(char dName, int dx, int dy) {
+        this.dName = dName;
+        this.dx = dx;
+        this.dy = dy;
+    }
+}
+
+class Solution {
+    public boolean isValid(int x, int y, int[][] mat) {
+        return x >= 0 && x < mat.length && y >= 0 && y < mat[0].length && mat[x][y] == 1;
+    }
+
+    public void solve(int x, int y, StringBuilder path, List<String> res, int[][] mat, List<Choice> choices) {
+        if (x == mat.length - 1 && y == mat[0].length - 1) {
+            res.add(path.toString());
+            return;
+        }
+        for (Choice choice : choices) {
+            int newX = x + choice.dx;
+            int newY = y + choice.dy;
+
+            if (isValid(newX, newY, mat)) {
+                mat[x][y] = 0; // Mark as visited
+                path.append(choice.dName);
+                solve(newX, newY, path, res, mat, choices);
+                mat[x][y] = 1; // Unmark as visited
+                path.deleteCharAt(path.length() - 1);
+            }
+        }
+    }
+
+    public List<String> findPath(int[][] mat) {
+        StringBuilder path = new StringBuilder();
+        List<String> res = new ArrayList<>();
+        List<Choice> choices = new ArrayList<>();
+        choices.add(new Choice('U', -1, 0));
+        choices.add(new Choice('D', 1, 0));
+        choices.add(new Choice('L', 0, -1));
+        choices.add(new Choice('R', 0, 1));
+
+        if (mat[0][0] == 1) {
+            solve(0, 0, path, res, mat, choices);
+        }
+
+        return res;
+    }
+}
+
+public class RateInmaze {
+
+}

Recursion/Trying_out_all_Combos_Hard/Sudoku_Solver.java

@@ -1,4 +1,4 @@
-package Recursion.Trying_out_all_Combos_Hard;
+
 
 public class Sudoku_Solver {
     public static boolean solve(char[][] board){