LeetCode: Text Justification

Problem Description:

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.

Corner Cases:

  • A line other than the last line might contain only one word. What should you do in this case?
    In this case, that line should be left-justified.

Solution and Precautions:

This is just a simulation problem, and there are only two kinds of justification: (1) left justified when there is only one word in that line or this is the last line (2) left and right justified in other cases. Read as many words as possible to fill one line with the constraint of the length.

Written on May 26, 2013