Check out the resources on the page's right side to learn more about linked lists. The video tutorial is by Gayle Laakmann McDowell, author of the best-selling interview book Cracking the Coding Interview.
A linked list is said to contain a cycle if any node is visited more than once while traversing the list. For example, in the following graph there is a cycle formed when node points back to node .
Function Description
Complete the function has_cycle in the editor below. It must return a boolean true if the graph contains a cycle, or false.
has_cycle has the following parameter(s):
- : a pointer to a Node object that points to the head of a linked list.
Note: If the list is empty, will be null.
Input Format
There is no input for this challenge. A random linked list is generated at runtime and passed to your function.
Constraints
Output Format
If the list contains a cycle, your function must return true. If the list does not contain a cycle, it must return false. The binary integer corresponding to the boolean value returned by your function is printed to stdout by our hidden code checker.
Sample Input
The following linked lists are passed as arguments to your function:
Sample Output
0
1
Explanation
- The first list has no cycle, so we return false and the hidden code checker prints to stdout.
- The second list has a cycle, so we return true and the hidden code checker prints to stdout.