Added codes for 13 Feb

GeeksForGeeks/February/13-2-24/GFG.java

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+//{ Driver Code Starts
+//Initial Template for Java
+
+import java.io.*;
+import java.util.*;
+import java.math.*;
+
+class Node{
+    int val;
+    ArrayList<Node> neighbors;
+    public Node(){
+        val = 0;
+        neighbors = new ArrayList<>();
+    }
+
+    public Node(int val){
+        this.val = val;
+        neighbors = new ArrayList<>();
+    }
+
+    public Node(int val, ArrayList<Node> neighbors){
+        this.val = val;
+        this.neighbors = neighbors;
+    }
+}
+
+class GFG{
+    static class FastReader{ 
+        BufferedReader br; 
+        StringTokenizer st; 
+
+        public FastReader(){ 
+            br = new BufferedReader(new InputStreamReader(System.in)); 
+        } 
+
+        String next(){ 
+            while (st == null || !st.hasMoreElements()){ 
+                try{ st = new StringTokenizer(br.readLine()); } catch (IOException  e){ e.printStackTrace(); } 
+            } 
+            return st.nextToken(); 
+        } 
+
+        String nextLine(){ 
+            String str = ""; 
+            try{ str = br.readLine(); } catch (IOException e) { e.printStackTrace(); } 
+            return str; 
+        } 
+
+        Integer nextInt(){
+            return Integer.parseInt(next());
+        }
+    }
+
+    static ArrayList<Node> bfs(Node src){
+        ArrayList<Node> ans = new ArrayList<>();
+        HashSet<Node> visited = new HashSet<>();
+        Queue<Node> q = new LinkedList<>();
+        q.add(src);
+        visited.add(src);
+
+        while(!q.isEmpty()){
+            Node u = q.poll();
+            ans.add(u);
+            ArrayList<Node> v = u.neighbors;
+            for(Node x : v){
+                if(!visited.contains(x)){
+                    visited.add(x);
+                    q.add(x);
+                }
+            }
+        }
+
+        return ans;
+    }
+
+    static boolean checkedClone(Node prev, Node new1){
+        ArrayList<Node> prevAns = bfs(prev);
+        ArrayList<Node> newAns = bfs(new1);
+        for(int i = 0; i < prevAns.size(); i++){
+            if(prevAns.get(i) == newAns.get(i))
+                return false;
+        }
+        return true;
+    }
+
+    public static void main(String[] args) throws IOException{
+        FastReader sc = new FastReader();
+        PrintWriter out = new PrintWriter(System.out);
+        int t = sc.nextInt();
+        while(t-- > 0){
+            int n = sc.nextInt();
+            Node root = null;
+            Node v[] = new Node[n];
+            for(int i = 0; i < n; i++) v[i] = new Node(i);
+            Solution ob = new Solution();
+            for(int i = 0; i < n; i++){
+                ArrayList<Node> li = new ArrayList<>();
+                String arr[] = sc.nextLine().split(" ");
+                for(String s : arr){
+                    li.add(v[Integer.parseInt(s)]);
+                }
+                v[i].neighbors = li;
+            }
+            ArrayList<Node> prev = bfs(v[0]);
+            Node ans = ob.cloneGraph(v[0]);
+            ArrayList<Node> now = bfs(ans);
+            out.println(checkedClone(v[0], ans) ? "1" :  "0");
+        }
+        out.flush();
+    }
+}
+// } Driver Code Ends
+
+
+//User function Template for Java
+
+
+/*
+    class Node{
+        int val;
+        ArrayList<Node> neighbors;
+        public Node(){
+            val = 0;
+            neighbors = new ArrayList<>();
+        }
+    
+        public Node(int val){
+            this.val = val;
+            neighbors = new ArrayList<>();
+        }
+    
+        public Node(int val, ArrayList<Node> neighbors){
+            this.val = val;
+            this.neighbors = neighbors;
+        }
+    }
+*/
+class Solution
+{
+    Node cloneGraph(Node source)
+    {
+        Queue<Node> q = new LinkedList<Node>();
+        q.add(source);
+
+        HashMap<Node,Node> hm = new HashMap<Node,Node>();
+
+        hm.put(source,new Node(source.val));
+
+        while (!q.isEmpty())
+        {
+            Node u = q.poll();
+
+            Node cloneNodeU = hm.get(u);
+            if (u.neighbors != null)
+            {
+                ArrayList<Node> v = u.neighbors;
+                for (Node graphNode : v)
+                {
+                    Node cloneNodeG = hm.get(graphNode);
+
+                    if (cloneNodeG == null)
+                    {
+                        q.add(graphNode);
+
+                        cloneNodeG = new Node(graphNode.val);
+                        hm.put(graphNode,cloneNodeG);
+                    }
+
+                    cloneNodeU.neighbors.add(cloneNodeG);
+                }
+            }
+        }
+
+        return hm.get(source);
+    }
+}

GeeksForGeeks/February/13-2-24/README.md

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+Time complexity - O(n+m)
+Space complexity - O(n)

LeetCode/February/13-2-24/README.md

@@ -0,0 +1,2 @@
+Time complexity - O(n)
+Space complexity - O(|word|)

LeetCode/February/13-2-24/Solution.java

@@ -0,0 +1,33 @@
+class Solution 
+{
+    public String firstPalindrome(String[] words) 
+    {
+        for (String word : words)
+        {
+            if (isPalindrome(word))
+                return word;
+        }
+
+        return "";
+    }
+
+    private boolean isPalindrome(String s) 
+    {
+        int i = 0;
+        int j = s.length() -1;
+
+        while (i <= j) 
+        {
+            if (s.charAt(i) == s.charAt(j)) 
+            {
+                i++;
+                j--;
+            }
+            else 
+            {
+                return false;
+            }
+        }
+        return true;
+    }
+}