edu.princeton.cs.algs4

Class DirectedEdge

java.lang.Object

edu.princeton.cs.algs4.DirectedEdge

public class DirectedEdge
extends java.lang.Object

The DirectedEdge class represents a weighted edge in an EdgeWeightedDigraph. Each edge consists of two integers (naming the two vertices) and a real-value weight. The data type provides methods for accessing the two endpoints of the directed edge and the weight.

For additional documentation, see Section 4.4 of Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.

Constructor Summary

Constructors

Constructor and Description
DirectedEdge(int v, int w, double weight) Initializes a directed edge from vertex v to vertex w with the given weight.

Method Summary

Modifier and Type	Method and Description
int	from() Returns the tail vertex of the directed edge.
static void	main(java.lang.String[] args) Unit tests the DirectedEdge data type.
int	to() Returns the head vertex of the directed edge.
java.lang.String	toString() Returns a string representation of the directed edge.
double	weight() Returns the weight of the directed edge.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

DirectedEdge

public DirectedEdge(int v,
                    int w,
                    double weight)

Initializes a directed edge from vertex v to vertex w with the given weight.

Parameters:

v - the tail vertex

w - the head vertex

weight - the weight of the directed edge

Throws:

java.lang.IllegalArgumentException - if either v or w is a negative integer

java.lang.IllegalArgumentException - if weight is NaN

Method Detail

from

public int from()

Returns the tail vertex of the directed edge.

Returns:

the tail vertex of the directed edge

to

public int to()

Returns the head vertex of the directed edge.

Returns:

the head vertex of the directed edge

weight

public double weight()

Returns the weight of the directed edge.

Returns:

the weight of the directed edge

toString

public java.lang.String toString()

Returns a string representation of the directed edge.

Overrides:

toString in class java.lang.Object

Returns:

a string representation of the directed edge

main

public static void main(java.lang.String[] args)

Unit tests the DirectedEdge data type.

Parameters:

args - the command-line arguments