roydevashish
diff --git a/‎F25LinkedList-1/AppendLastNToFirst.cpp‎
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diff --git a/‎F25LinkedList-1/DeleteNodeInLL.cpp‎
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+/*
+Title: Append Last N to First
+
+Problem statement
+You have been given a singly linked list of integers along with an integer 'N'. Write a function to 
+append the last 'N' nodes towards the front of the singly linked list and returns the new head to the list.
+
+Hint:
+Identify how many pointers you require and try traversing them to right places and connect nodes accordingly 
+also don't forget to disconnect what's required else it could create cycles.
+
+Detailed explanation ( Input/output format, Notes, Images )
+Input format :
+The first line contains an Integer 't' which denotes the number of test cases or queries to be run. Then the 
+test cases follow.
+    The first line of each test case or query contains the elements of the singly linked list separated by a single space. 
+    The second line contains the integer value 'N'. It denotes the number of nodes to be moved from last to the front of the singly linked list.
+
+Output format :
+For each test case/query, print the resulting singly linked list of integers in a row, separated by a single space.
+Output for every test case will be printed in a seperate line.
+
+Constraints :
+1 <= t <= 10^2
+0 <= M <= 10^5
+0 <= N < M
+
+Time Limit: 1sec
+Where 'M' is the size of the singly linked list.
+
+Remember/Consider :
+While specifying the list elements for input, -1 indicates the end of the singly linked list and hence, would never be a list element.
+
+Sample Input 1 :
+2
+1 2 3 4 5 -1
+3
+10 20 30 40 50 60 -1
+5
+
+Sample Output 1 :
+3 4 5 1 2
+20 30 40 50 60 10
+
+Sample Input 2 :
+1
+10 6 77 90 61 67 100 -1
+4
+
+Sample Output 2 :
+90 61 67 100 10 6 77 
+
+Explanation to Sample Input 2 :
+We have been required to move the last 4 nodes to the front of the list. Here, "90->61->67->100" is 
+the list which represents the last 4 nodes. When we move this list to the front then the remaining 
+part of the initial list which is, "10->6->77" is attached after 100. Hence, the new list formed 
+with an updated head pointing to 90.
+*/
+
+#include<iostream>
+using namespace std;
+
+class Node {
+public:
+	int data;
+	Node *next;
+	Node(int data) {
+		this->data = data;
+		this->next = NULL;
+	}
+};
+
+Node * appendLastNToFirst(Node * head, int n) {
+    if(head == NULL) {
+        return NULL;
+    }
+
+    int count = 0;
+    Node * tail = NULL;
+    Node * current = head;
+    while(current != NULL) {
+        count++;
+        tail = current;
+        current = current->next;
+    }
+
+    int pos = count - n;
+    int idx = 1;
+    Node * temp = head;
+    while(temp != NULL && idx < pos) {
+        idx++;
+        temp = temp->next;
+    }
+
+    tail->next = head;
+    head = temp->next;
+    temp->next = NULL;
+    return head;
+}
+
+Node *takeinput() {
+	int data;
+	cin >> data;
+	Node *head = NULL, *tail = NULL;
+	while (data != -1) {
+		Node *newnode = new Node(data);
+		if (head == NULL) {
+			head = newnode;
+			tail = newnode;
+		} else {
+			tail->next = newnode;
+			tail = newnode;
+		}
+		cin >> data;
+	}
+	return head;
+}
+
+void print(Node *head) {
+	Node *temp = head;
+	while (temp != NULL) {
+		cout << temp->data << " ";
+		temp = temp->next;
+	}
+	cout << endl;
+}
+
+int main() {
+	int t;
+	cin >> t;
+	while (t--) {
+		Node *head = takeinput();
+		int n;
+		cin >> n;
+		head = appendLastNToFirst(head, n);
+		print(head);
+	}
+	return 0;
+}
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+/*
+Title: Delete a node from Linked List
+
+Problem statement
+You have been given a linked list of integers. Your task is to write a function that deletes a node
+from a given position, 'POS'.
+
+Note :
+Assume that the Indexing for the linked list always starts from 0.
+If the position is greater than or equal to the length of the linked list, you should return the 
+same linked list without any change.
+
+Illustration :
+The following images depict how the deletion has been performed.
+Image-I :
+Head -> 10 -> 20 -> 30 -> 40 -> 50 -> NULL
+
+Image-II :
+Head -> 10 -> 20 -> 40 -> 50 -> NULL
+                30 ->|
+Head -> 10 -> 20 -> 40 -> 50 -> NULL
+
+Detailed explanation ( Input/output format, Notes, Images )
+Input format :
+The first line contains the elements of the linked list separated by a single space. 
+The second line contains the integer value of 'POS'. It denotes the position in the linked list from 
+where the node has to be deleted.
+
+Remember/Consider :
+While specifying the list elements for input, -1 indicates the end of the singly linked list and hence, 
+would never be a list element
+
+Output format :
+Print the resulting linked list of integers in a row, separated by a single space.
+Note:
+
+You are not required to print the output, it has already been taken care of. Just implement the function. 
+
+Sample Input 1 :
+3 4 5 2 6 1 9 -1
+3
+
+Sample Output 1 :
+3 4 5 6 1 9
+
+Explanation of Sample Output 1 :
+The data in the node with index 3 is 2 which has been removed.
+
+Sample Input 2 :
+3 4 5 2 6 1 9 -1
+0
+
+Sample Output 2 :
+4 5 2 6 1 9
+
+Constraints :
+0 <= N <= 10^5
+POS >= 0
+
+Time Limit: 1sec
+Expected Complexity :
+Time Complexity  : O(N)
+Space Complexity  : O(1)
+*/
+
+#include<iostream>
+#include<fstream>
+#include<vector>
+#include<cmath>
+#include<algorithm>
+#include<bits/stdc++.h>
+using namespace std;
+
+class Node {
+public:
+	int data;
+	Node *next;
+	Node(int data) {
+		this->data = data;
+		this->next = NULL;
+	}
+};
+
+Node *deleteNode(Node *head, int pos) {
+    // Write your code here.
+    if(head == NULL) {
+        return NULL;
+    }
+
+    int idx = 0;
+    Node * prev = NULL;
+    Node * current = head;
+
+    while(current != NULL && idx < pos) {
+        idx++;
+        prev = current;
+        current = current->next;
+    }
+
+    if(pos == 0) {
+        return head->next;
+    }
+
+    if(idx == pos) {
+        prev->next = current->next;
+    }
+
+    return head;
+}
+
+
+class Runner {
+    int pos;
+    Node *head = NULL;
+public:
+    
+    void takeInput() {
+        int data;
+        cin >> data;
+        Node *tail = NULL;
+        while (data != -1) {
+            Node *newNode = new Node(data);
+            if (head == NULL) {
+                head = newNode;
+                tail = newNode;
+            } else {
+                tail->next = newNode;
+                tail = newNode;
+            }
+            cin >> data;
+        }
+		cin >> pos;
+    }
+
+    Node * copyll(Node *chead) {
+        if(chead == NULL)return NULL;
+        Node *nhead= NULL;
+
+        Node *tail = NULL;
+        while (chead != NULL) {
+            Node *newNode = new Node(chead->data);
+            if (nhead == NULL) {
+                nhead = newNode;
+                tail = newNode;
+            } else {
+                tail->next = newNode;
+                tail = newNode;
+            }
+            chead=chead->next;
+        }
+        return nhead;
+    }
+
+    void print(Node *head) {
+        Node *temp = head;
+        while (temp != NULL) {
+            cout << temp->data << " ";
+            temp = temp->next;
+        }
+        cout << endl;
+    }
+    
+    void execute() {
+        Node *copyhead = copyll(head);
+        copyhead = deleteNode(copyhead, pos);
+        while(copyhead!=NULL) {
+            Node* temp=copyhead;
+            copyhead=copyhead->next;
+            delete temp;
+        }
+    }
+
+    void executeAndPrintOutput() {
+        Node *copyhead = copyll(head);
+        copyhead = deleteNode(copyhead, pos);
+		print(copyhead);
+        while(copyhead!=NULL) {
+            Node* temp=copyhead;
+            copyhead=copyhead->next;
+            delete temp;
+        }
+    }
+};
+
+int main() {   
+    Runner runner;
+    runner.takeInput();
+    runner.executeAndPrintOutput();   
+    return 0;
+}