[Leetcode] Text Justification

The code is also available here https://gist.github.com/pyemma/b8b0f771085823ec4b87

/*
 * Author: Yang Pei
 * Problem: Text Justification
 * Source: https://oj.leetcode.com/problems/text-justification/
 * 
 * Note:
 * Given an array of words and a length L, format the text such that each line has exactly L characters and is fully (left and right) justified.
 * You should pack your words in a greedy approach; that is, pack as many words as you can in each line. Pad extra spaces ' ' when necessary so that each line has exactly L characters.
 * Extra spaces between words should be distributed as evenly as possible. If the number of spaces on a line do not divide evenly between words, the empty slots on the left will be assigned more spaces than the slots on the right.
 * For the last line of text, it should be left justified and no extra space is inserted between words.
 * 
 * For example,
 * words: ["This", "is", "an", "example", "of", "text", "justification."]
 * L: 16.
 * 
 * Return the formatted lines as:
 * [
 * "This    is    an",
 * "example  of text",
 * "justification.  
 * ]
 * Note: Each word is guaranteed not to exceed L in length.
 * 
 * Solution:
 * Use one function to determine the words, use one function to make the line.
 * 
 * Corner case:
 * The last line and the line with only one words, we should left-justified.
 */
import java.util.*;

public class TextJustification {
 private int wordCount(String[] words, int beg, int L) {
  // return the first of next line's word's index
  int count = 0;
  int i = beg;
  for(i = beg; i < words.length; i++) {
   count = count + words[i].length();
   if(count > L)
    break;
   count = count + 1;
  }
  return i;
 }
 
 private String newLine(String[] words, int beg, int end, int L) {
  int count = 0;
  for(int i = beg; i < end; i++)
   count = count + words[i].length();
  int number = end - beg;
  int blank = number == 1 ? ((L - count) / (number - 1)) : L - count;
  int extra = number == 1 ? ((L - count) % (number - 1)) : 0;
  String bl = "";
  for(int i = 0; i < blank; i++)
   bl = bl + " ";
  StringBuffer line = new StringBuffer();
  for(int i = beg; i < end; i++) {
   line.append(words[i]);
   if(beg != i && i == end - 1)
    break;
   line.append(bl);
   if(extra > 0) {
    line.append(" ");
    extra--;
   }
  }
  return line.toString();
 }
 
 private String lastLine(String[] words, int beg, int L) {
  StringBuffer line = new StringBuffer();
  for(int i = beg; i < words.length; i++) {
   line.append(words[i]);
   if(i != words.length - 1)
    line.append(" ");
  }
  int blank = L - line.length();
  for(int i = 0; i < blank; i++)
   line.append(" ");
  return line.toString();
 }
 
 public List<String> fullJustify(String[] words, int L) {
  int ind = 0;
  List<String> result = new ArrayList<String>();
  while(ind < words.length) {
   int beg = ind;
   ind = wordCount(words, beg, L);
   if(ind == words.length)
    result.add(lastLine(words, beg, L));
   else
    result.add(newLine(words, beg, ind, L));
  }
  return result;
 }
}