Cycle

java.lang.Object
- edu.princeton.cs.algs4.Cycle

```
public class Cycle
extends java.lang.Object
```
The Cycle class represents a data type for determining whether an undirected graph has a simple cycle. The hasCycle operation determines whether the graph has a cycle and, if so, the cycle operation returns one.
This implementation uses depth-first search. The constructor takes time proportional to V + E (in the worst case), where V is the number of vertices and E is the number of edges. Afterwards, the hasCycle operation takes constant time; the cycle operation takes time proportional to the length of the cycle.
For additional documentation, see Section 4.1 of Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.

构造器概要

构造器
构造器说明

Cycle(Graph G)
Determines whether the undirected graph G has a cycle and, if so, finds such a cycle.

方法概要

修饰符和类型	方法	说明
`java.lang.Iterable<java.lang.Integer>`	`cycle()`	Returns a cycle in the graph `G`.
`boolean`	`hasCycle()`	Returns true if the graph `G` has a cycle.
`static void`	`main(java.lang.String[] args)`	Unit tests the `Cycle` data type.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 构造器详细资料
  - Cycle
```
public Cycle(Graph G)
```
    Determines whether the undirected graph G has a cycle and, if so, finds such a cycle.
    
    参数:
    
    G - the undirected graph
- 方法详细资料
  - hasCycle
```
public boolean hasCycle()
```
    Returns true if the graph G has a cycle.
    
    返回:
    
    true if the graph has a cycle; false otherwise
  - cycle
```
public java.lang.Iterable<java.lang.Integer> cycle()
```
    Returns a cycle in the graph G.
    
    返回:
    
    a cycle if the graph G has a cycle, and null otherwise
  - main
```
public static void main(java.lang.String[] args)
```
    Unit tests the Cycle data type.
    
    参数:
    
    args - the command-line arguments