85 lines
1.4 KiB
C++
85 lines
1.4 KiB
C++
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#include <iostream>
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using namespace std;
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class Node {
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public:
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int data;
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Node* next;
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};
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class NodeOperation {
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public:
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// Function to add a new node
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void pushNode(class Node** head_ref, int data_val)
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{
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// Allocate node
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class Node* new_node = new Node();
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// Put in the data
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new_node->data = data_val;
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// Link the old list off the new node
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new_node->next = *head_ref;
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// move the head to point to the new node
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*head_ref = new_node;
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}
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// A utility function to print a given linked list
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void printNode(class Node* head)
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{
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while (head != NULL) {
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cout << head->data << "->";
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head = head->next;
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}
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cout << "NULL" << endl;
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}
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/* Utility Function to find length of linked list */
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int getLen(class Node* head)
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{
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int len = 0;
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class Node* temp = head;
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while (temp) {
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len++;
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temp = temp->next;
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}
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return len;
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}
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void printMiddle(class Node* head)
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{
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if (head) {
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// find length
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int len = getLen(head);
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class Node* temp = head;
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// trvaers till we reached half of length
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int midIdx = len / 2;
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while (midIdx--) {
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temp = temp->next;
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}
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// temp will be storing middle element
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cout << "The middle element is [" << temp->data
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<< "]" << endl;
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}
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}
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};
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// Driver Code
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int main()
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{
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class Node* head = NULL;
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class NodeOperation* temp = new NodeOperation();
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for (int i = 5; i > 0; i--) {
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temp->pushNode(&head, i);
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temp->printNode(head);
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temp->printMiddle(head);
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}
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return 0;
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}
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