Java/DataStructures/Lists/SinglyLinkedList.java at master · classloader/Java · GitHub

History

178 lines (154 loc) · 4.12 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

package DataStructures.Lists;

/**

* This class implements a SinglyLinked List. This is done

* using SinglyLinkedList class and a LinkForLinkedList Class.

* <p>

* A linked list is similar to an array, it hold values.

* However, links in a linked list do not have indexes. With

* a linked list you do not need to predetermine it's size as

* it grows and shrinks as it is edited. This is an example of

* a singly linked list. Elements can only be added/removed

* at the head/front of the list.

public class SinglyLinkedList {

/**

* Head refer to the front of the list

private Node head;

/**

* This method inserts an element at the head

* @param x Element to be added

public void insertHead(int x) {

Node newNode = new Node(x);

newNode.next = head;

head = newNode;

}

/**

* Inserts a new node at a specified position

* @param data data to be stored in a new node

* @param position position at which a new node is to be inserted

public void insertNth(int data, int position) {

if (position < 0 || position > getSize()) {

throw new RuntimeException("position less than zero or position more than the count of list");

} else if (position == 0)

insertHead(data);

else {

Node cur = head;

Node node = new Node(data);

for (int i = 1; i < position; ++i) {

cur = cur.next;

}

node.next = cur.next;

cur.next = node;

}

/**

* This method deletes an element at the head

* @return The element deleted

public void deleteHead() {

if (isEmpty()) {

throw new RuntimeException("The list is empty!");

}

head = head.next;

}

/**

* This method deletes an element at Nth position

public void deleteNth(int position) {

if (position < 0 || position >= getSize()) {

throw new RuntimeException("position less than zero or position more than the count of list");

} else if (position == 0)

deleteHead();

else {

Node cur = head;

for (int i = 1; i < position; ++i) {

cur = cur.next;

}

cur.next = cur.next.next;

}

/**

* Checks if the list is empty

* @return true is list is empty

public boolean isEmpty() {

return getSize() == 0;

}

/**

* Prints contents of the list

public void display() {

Node current = head;

while (current != null) {

System.out.print(current.value + " ");

current = current.next;

}

System.out.println();

}

/**

* Returns the size of the linked list

public int getSize() {

if (head == null)

return 0;

else {

Node current = head;

int size = 1;

while (current.next != null) {

current = current.next;

size++;

}

return size;

}

/**

* Main method

* @param args Command line arguments

public static void main(String args[]) {

SinglyLinkedList myList = new SinglyLinkedList();

assert myList.isEmpty();

myList.insertHead(5);

myList.insertHead(7);

myList.insertHead(10);

myList.display(); // 10 -> 7 -> 5

myList.deleteHead();

myList.display(); // 7 -> 5

myList.insertNth(11, 2);

myList.display(); // 7 -> 5 -> 11

myList.deleteNth(1);

myList.display(); // 7-> 11

}

/**

* This class is the nodes of the SinglyLinked List.

* They consist of a value and a pointer to the node

* after them.

class Node {

/**

* The value of the node

int value;

/**

* Point to the next node

Node next;

/**

* Constructor

* @param value Value to be put in the node

Node(int value) {

this.value = value;

this.next = null;

}

Java/DataStructures/Lists/SinglyLinkedList.java at master · classloader/Java · GitHub

Expand file tree

Breadcrumbs

SinglyLinkedList.java

Latest commit

History

Breadcrumbs

SinglyLinkedList.java

File metadata and controls