I got couple errors for my program and need help. See if you can help.
The errors states:
LinkList.java.29: variable trailp might not have been initialized trailp.next = new Node(B, p); ^ LinkList.java.44: variable trailp might not have been initialized trailp.next = p; ^ Here is my code:
import java.io.*; import java.util.*;
public class LinkList { private Node first;
class Node { int data; Node next;
public Node (int iData, Node iNext) { data = iData; next = iNext; } } // end class Node
public void insert(int B) { Node p = first, trailp; while (p != null && p.data < B) { trailp = p; p = p.next; } if (p == first) first = new Node(B, first); else trailp.next = new Node(B, p); } //-----------------------------------------------------------------------
public boolean delete(int B) { Node p = first, trailp; while ( p != null && p.data != B) { trailp = p; p = p.next; } if (p == null) return false; if (p == first) first = first.next; else trailp.next = p.next;
public LinkList copy( ) { LinkList C = new LinkList( );
if (first == null) { C.first = null; return C; } C.first = new Node(first.data, null); Node last = C.first; Node p = first.next; Node q;
while (p != null) { q = new Node(p.data, null); last.next = q; last = q; p = p.next; } return C; } //-----------------------------------------------------------------------
public void merge(LinkList L1, LinkList L2, LinkList L3) { Node p = first; if (L1.first == null) { L3.first = L2.first; return; } if (L2.first == null) { L3.first = L1.first; return; } Node p1, p2, last; if (L1.first.data < L2.first.data) { L3.first = L1.first; p1 = L1.first.next; last = L3.first; p2 = L2.first; } else { L3.first = L2.first; p2 = L2.first.next; last = L3.first; p1 = L1.first; }
while (p1 != null && p2 != null) { if (p1.data < p2.data) { last.next = p; last = p1; p1 = p1.next; } else { last.next = p2; last = p2; p2 = p2.next; } } if (p1 == null) last.next = p2; else last.next = p1; return;
} // end merge //-----------------------------------------------------------------------
public static void main(String[] arg) throws IOException { BufferedReader br = new BufferedReader(new FileReader(arg[0])); String line = br.readLine(); StringTokenizer data; int cToken;
LinkList list = new LinkList();
while (line != null) { data = new StringTokenizer(line); cToken = data.countTokens(); for (int i = 0; i < cToken; i++) list.insert(Integer.parseInt(data.nextToken())); line = br.readLine(); }
// method sort the list //list.sortList();
// method to print list.output(arg[0], arg[1]); } //-----------------------------------------------------------------------
public void output(String inFile, String outFile) throws IOException { PrintWriter pw = new PrintWriter(new FileWriter(outFile)); pw.println("Input file: " + inFile + "\nOutput file: " + outFile + "\nWritten by: Tom Zang\n"); pw.println("Output result"); pw.println(); int count = 0; for (Node cursor = first ; cursor != null ; cursor = cursor.next) { pw.println(cursor); count++; } for (int i = 0; i < 80; i++) pw.print("_"); pw.println(); pw.println(); pw.println("Size of the list = " + count); pw.close(); } } // end LinkListTest class
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