{"id":26870,"date":"2017-12-26T20:38:35","date_gmt":"2017-12-26T15:08:35","guid":{"rendered":"https:\/\/www.wikitechy.com\/technology\/?p=26870"},"modified":"2017-12-26T20:38:35","modified_gmt":"2017-12-26T15:08:35","slug":"c-algorithm-find-length-linked-list-iterative-recursive-2","status":"publish","type":"post","link":"https:\/\/www.wikitechy.com\/technology\/c-algorithm-find-length-linked-list-iterative-recursive-2\/","title":{"rendered":"Cpp Algorithm – Find Length of a Linked List both Iterative and Recursive"},"content":{"rendered":"

Write a C function to count number of nodes in a given singly linked list.<\/p>\n

\"C<\/p>\n

For example, the function should return 5 for linked list 1->3->1->2->1.<\/p>\n

Iterative Solution<\/strong><\/p>\n

1) Initialize count as 0 \r\n2) Initialize a node pointer, current = head.\r\n3) Do following while current is not NULL\r\n     a) current = current -> next\r\n     b) count++;\r\n4) Return count<\/pre>\n
C++ Programming:<\/strong><\/p>\n
 
 <\/div> 
\/\/ Iterative C program to find length or count of nodes in a linked list#include<stdio.h>#include<stdlib.h> \/* Link list node *\/struct node{    int data;    struct node* next;}; \/* Given a reference (pointer to pointer) to the head  of a list and an int, push a new node on the front  of the list. *\/void push(struct node** head_ref, int new_data){    \/* allocate node *\/    struct node* new_node =            (struct node*) malloc(sizeof(struct node));     \/* put in the data  *\/    new_node->data  = new_data;     \/* link the old list off the new node *\/    new_node->next = (*head_ref);     \/* move the head to point to the new node *\/    (*head_ref)    = new_node;} \/* Counts no. of nodes in linked list *\/int getCount(struct node* head){    int count = 0;  \/\/ Initialize count    struct node* current = head;  \/\/ Initialize current    while (current != NULL)    {        count++;        current = current->next;    }    return count;} \/* Drier program to test count function*\/int main(){    \/* Start with the empty list *\/    struct node* head = NULL;     \/* Use push() to construct below list     1->2->1->3->1  *\/    push(&head, 1);    push(&head, 3);    push(&head, 1);    push(&head, 2);    push(&head, 1);     \/* Check the count function *\/    printf("count of nodes is %d", getCount(head));    return 0;}<\/code><\/pre> <\/div>\n[ad type=”banner”]\n
Output:<\/strong><\/p>\n
count of nodes is 5<\/pre>\n
Recursive Solution<\/strong><\/p>\n
int getCount(head)<\/strong>\r\n1) If head is NULL, return 0.\r\n2) Else return 1 + getCount(head->next)<\/pre>\n
C++ Programming:<\/strong><\/p>\n
 
 <\/div> 
\/\/ Recursive C program to find length or count of nodes in a linked list#include<stdio.h>#include<stdlib.h> \/* Link list node *\/struct node{    int data;    struct node* next;}; \/* Given a reference (pointer to pointer) to the head  of a list and an int, push a new node on the front  of the list. *\/void push(struct node** head_ref, int new_data){    \/* allocate node *\/    struct node* new_node =            (struct node*) malloc(sizeof(struct node));     \/* put in the data  *\/    new_node->data  = new_data;     \/* link the old list off the new node *\/    new_node->next = (*head_ref);     \/* move the head to point to the new node *\/    (*head_ref)    = new_node;} \/* Counts the no. of occurences of a node   (search_for) in a linked list (head)*\/int getCount(struct node* head){    \/\/ Base case    if (head == NULL)        return 0;     \/\/ count is 1 + count of remaining list    return 1 + getCount(head->next);} \/* Drier program to test count function*\/int main(){    \/* Start with the empty list *\/    struct node* head = NULL;     \/* Use push() to construct below list     1->2->1->3->1  *\/    push(&head, 1);    push(&head, 3);    push(&head, 1);    push(&head, 2);    push(&head, 1);     \/* Check the count function *\/    printf("count of nodes is %d", getCount(head));    return 0;}<\/code><\/pre> <\/div>\n[ad type=”banner”]\n
Output:<\/strong><\/p>\n
count of nodes is 5<\/pre>\n","protected":false},"excerpt":{"rendered":"
C++ Algorithm – Find Length of a Linked List both Iterative and Recursive – Linked List – Write a C function to count number of nodes in a given singly<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[83515,79476,79478],"tags":[72483,80240,80236,80239,80231,80237,80241,80232,80238,80235,80234,80230,80233],"class_list":["post-26870","post","type-post","status-publish","format-standard","hentry","category-c-programming-3","category-linked-list","category-singly-linked-list","tag-c-linked-list","tag-find-length-of-linked-list-java","tag-geeksforgeeks","tag-get-length-of-linked-list-python","tag-how-to-calculate-the-length-of-linked-list-without-using-counter-in-java","tag-how-to-find-the-length-of-a-linked-list-python","tag-length-of-linked-list-c","tag-length-of-linked-list-python","tag-linked-list-implementation-in-python","tag-linkedlist-java","tag-recursive-linked-list-java","tag-size-of-linked-list-c","tag-what-is-a-class-loader-what-does-it-do"],"_links":{"self":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts\/26870","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/comments?post=26870"}],"version-history":[{"count":0,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts\/26870\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/media?parent=26870"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/categories?post=26870"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/tags?post=26870"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}