Slow and Fast Pointers in Single Linked List:
- Slow pointer and fast pointer are simply the names given to two pointer variables.
- The only difference is that, slow pointer travels the linked list one node at a time where as a fast pointer travels the linked list two nodes at a time.
| #include<stdio.h> #include<stdlib.h> struct Node { int data; struct Node* link; }; struct Node* root=NULL; int length(); struct Node* create(int); struct Node* insert(struct Node*,int); int middle(); void display(); int main() { int i,x; for(i=10 ; i<=100 ; i+=10) { root = insert(root, i); } x = middle(); printf(“Middle value : %d\n”,x); return 0; } struct Node* create(int ele) { struct Node* temp; temp=(struct Node*)malloc(sizeof(struct Node)); temp->data=ele; temp->link=NULL; return temp; } struct Node* insert(struct Node* temp, int ele) { if(temp==NULL) { return create(ele); } else { temp->link = insert(temp->link,ele); } return temp; } int middle() { struct Node *fast, *slow; slow=fast=root; while(fast->link!=NULL && fast->link->link!=NULL) { slow=slow->link; fast=fast->link->link; } return slow->data; } |