| 27 | } |
| 28 | |
| 29 | int detectLoop(Node* head) |
| 30 | { |
| 31 | Node *fast_pointer = head; |
| 32 | Node *slow_pointer = head; |
| 33 | |
| 34 | |
| 35 | /* |
| 36 | Check for null value for fast_pointer and fast_pointer->next |
| 37 | So to avoid segmentation fault error for case in which there |
| 38 | is no loop for both even and odd number of elements |
| 39 | */ |
| 40 | while(fast_pointer && fast_pointer->next) |
| 41 | { |
| 42 | slow_pointer = slow_pointer->next; |
| 43 | fast_pointer = fast_pointer->next->next; |
| 44 | if(fast_pointer == slow_pointer) |
| 45 | { |
| 46 | return 1; |
| 47 | } |
| 48 | } |
| 49 | |
| 50 | return 0; |
| 51 | } |
| 52 | |
| 53 | /* Driver code*/ |
| 54 | int main() |