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docs: update the whole repository

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* fix some bugs
* delete duplicate files
* format code
This commit is contained in:
yanglbme
2019-05-09 19:32:54 +08:00
parent 163db8521a
commit 29948363da
368 changed files with 4372 additions and 30841 deletions
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34
DataStructures/Graphs/Graphs.java
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@ -1,8 +1,10 @@
package DataStructures.Graphs;
import java.util.ArrayList;
import java.lang.StringBuilder;
class AdjacencyListGraph<E extends Comparable<E>> {
ArrayList<Vertex> verticies;
public AdjacencyListGraph() {
@ -19,7 +21,7 @@ class AdjacencyListGraph<E extends Comparable<E>> {
}
public boolean addAdjacentVertex(Vertex to) {
for (Vertex v: adjacentVerticies) {
for (Vertex v : adjacentVerticies) {
if (v.data.compareTo(to.data) == 0) {
return false; // the edge already exists
}
@ -46,12 +48,12 @@ class AdjacencyListGraph<E extends Comparable<E>> {
* verticies
*
* @param from the data of the vertex the edge is from
* @param to the data of the vertex the edge is going to
* @param to the data of the vertex the edge is going to
* @return returns false if the edge doesn't exist, returns true if the edge exists and is removed
*/
public boolean removeEdge(E from, E to) {
Vertex fromV = null;
for (Vertex v: verticies) {
for (Vertex v : verticies) {
if (from.compareTo(v.data) == 0) {
fromV = v;
break;
@ -60,17 +62,18 @@ class AdjacencyListGraph<E extends Comparable<E>> {
if (fromV == null) return false;
return fromV.removeAdjacentVertex(to);
}
/**
* this method adds an edge to the graph between two specified
* verticies
* verticies
*
* @param from the data of the vertex the edge is from
* @param to the data of the vertex the edge is going to
* @param to the data of the vertex the edge is going to
* @return returns true if the edge did not exist, return false if it already did
*/
public boolean addEdge(E from, E to) {
Vertex fromV = null, toV = null;
for (Vertex v: verticies) {
for (Vertex v : verticies) {
if (from.compareTo(v.data) == 0) { // see if from vertex already exists
fromV = v;
} else if (to.compareTo(v.data) == 0) { // see if to vertex already exists
@ -91,17 +94,18 @@ class AdjacencyListGraph<E extends Comparable<E>> {
/**
* this gives a list of verticies in the graph and their adjacencies
*
*
* @return returns a string describing this graph
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
for (Vertex v: verticies) {
for (Vertex v : verticies) {
sb.append("Vertex: ");
sb.append(v.data);
sb.append("\n");
sb.append("Adjacent verticies: ");
for (Vertex v2: v.adjacentVerticies) {
for (Vertex v2 : v.adjacentVerticies) {
sb.append(v2.data);
sb.append(" ");
}
@ -112,18 +116,18 @@ class AdjacencyListGraph<E extends Comparable<E>> {
}
public class Graphs {
public static void main(String args[]) {
AdjacencyListGraph<Integer> graph = new AdjacencyListGraph<>();
public static void main(String args[]) {
AdjacencyListGraph<Integer> graph = new AdjacencyListGraph<>();
assert graph.addEdge(1, 2);
assert graph.addEdge(1, 5);
assert graph.addEdge(2, 5);
assert !graph.addEdge(1, 2);
assert !graph.addEdge(1, 2);
assert graph.addEdge(2, 3);
assert graph.addEdge(3, 4);
assert graph.addEdge(4, 1);
assert !graph.addEdge(2, 3);
System.out.println(graph);
}
}