Nthnodefromend.cpp

1.linked list/Nthnodefromend.cpp

@@ -0,0 +1,73 @@
+
+#include <bits/stdc++.h>
+using namespace std;
+
+/* Link list Node */
+struct Node {
+  int data;
+  struct Node *next;
+  Node(int x) {
+    data = x;
+    next = NULL;
+  }
+};
+int getNthFromLast(struct Node* head, int n);
+
+/* struct Node {
+  int data;
+  struct Node *next;
+  Node(int x) {
+    data = x;
+    next = NULL;
+  }
+};
+*/
+
+//Function to find the data of nth node from the end of a linked list.
+class Solution{
+public:
+    int getNthFromLast(Node *head, int n)
+    {
+        Node *slow=head;
+    Node *fast=head;
+    for(int i=0;i<n;i++)
+    {
+         if(fast==NULL)
+             return -1;
+         fast=fast->next;
+    }
+    while(fast!=NULL)
+    {
+        slow=slow->next;
+        fast=fast->next;
+    }
+    return slow->data;
+    }
+};
+
+
+int main()
+{
+  int T,i,n,l,k;
+
+    cin>>T;
+
+    while(T--){
+    struct Node *head = NULL,  *tail = NULL;
+
+        cin>>n>>k;
+        int firstdata;
+        cin>>firstdata;
+        head = new Node(firstdata);
+        tail = head;
+        for(i=1;i<n;i++)
+        {
+            cin>>l;
+            tail->next = new Node(l);
+            tail = tail->next;
+        }
+    Solution obj;
+    cout<<obj.getNthFromLast(head, k)<<endl;
+    }
+    return 0;
+}