Find the number of nodes in single link list

Now, we will see how to find the number of nodes in single link list:

Algorithm to find number of nodes in the list:

Set TEMP = START
Set COUNT = 0
While (TEMP != NULL)
- COUNT = COUNT + 1
- TEMP = TEMP->NEXT
End While;
Return COUNT

Function to count number of node in link list:


int countNodes(NODE **start){
 NODE *temp = *start;
 int count = 0;
 while(temp != NULL){
  count++;
  temp = temp->next;
 }
 return count;
}

Program to count number of nodes in the link list:


#include <stdio.h>
#include <malloc.h>

struct node{
 int info;
 struct node *next;
};
typedef struct node NODE;

void insertAtFirst(NODE **, int);
int countNodes(NODE **);

int main(){
 
 NODE *start = NULL;
 
 insertAtFirst(&start, 4);
 insertAtFirst(&start, 5);
 insertAtFirst(&start, 6);
 printf("\nThe list have %d nodes\n", countNodes(&start));
 return 0;
}

int countNodes(NODE **start){
 NODE *temp = *start;
 int count = 0;
 while(temp != NULL){
  count++;
  temp = temp->next;
 }
 return count;
}

void insertAtFirst(NODE **start, int info){
 NODE *ptr = (NODE*) malloc(sizeof(NODE));
 ptr->info = info;
 ptr->next = *start;
 *start = ptr;
}

The list have 3 nodes

Comments

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