LeetCode, leetcodeoj

LeetCode, leetcodeoj

Question:

Given an array of words and a lengthL, Format the text such that each line has exactlyLCharacters and is fully (left and right) justified.

You shoshould pack your words in a greedy approach; that is, pack as your words as you can in each line. Pad extra spaces' 'When necessary so that each line has exactlyLCharacters.

Extra spaces between words shoshould 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 shocould 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:

[   "This    is    an",   "example  of text",   "justification.  "]

Note:Each word is guaranteed not to exceedLIn length.

Idea: linear forward

package manipulation;import java.util.ArrayList;import java.util.List;public class TextJustification {    public List<String> fullJustify(String[] words, int maxWidth) {        List<String> res = new ArrayList<String>();        int n = words.length;        int i = 0;        int len = 0;        int start = 0;        for (; i < n; ++i) {                 if (len + words[i].length() + (i == start ? 0 : 1) > maxWidth) {                justify(words, start, i - 1, res, maxWidth);                start = i;                len = 0;            }            len += words[i].length() + (i == start ? 0 : 1);        }        justify(words, start, n - 1, res, maxWidth);        return res;    }        private void justify(String[] words, int start, int end, List<String> res, int L) {        int count = 0;        int total = 0;        for (int i = start; i <= end; ++i) {            ++count;            total += words[i].length();        }        int rem = L - total;        // Only one word in this line        if (count == 1) {            String space = "";            for (int i = 0; i < rem; ++i) space += " ";            res.add(words[start] + space);        } else if (end == words.length - 1) { // This is the last line            String s = words[start];            for (int i = 1; i <= count - 1; ++i) {                s += " " + words[start + i];            }            for (int i = 0; i < rem - count + 1; ++i) s+= " ";            res.add(s);        } else { // General case            int avg = rem / (count - 1);            int leftMore = rem - avg * (count  - 1);            String s = words[start];            for (int i = 1; i <= count - 1; ++i) {                for (int j = 0; j < avg; ++j) s += " ";                s += leftMore-- > 0 ? " " : "";                s += words[start + i];            }            res.add(s);        }    }        public static void main(String[] args) {        // TODO Auto-generated method stub        String[] words = { "This", "is", "an", "example", "of", "text", "justification." };        TextJustification t = new TextJustification();        for (String s : t.fullJustify(words, 16)){            System.out.println(s);        }    }}