# 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.
class Solution(object):
def fullJustify(self, words, maxWidth):
"""
:type words: List[str]
:type maxWidth: int
:rtype: List[str]
"""
lines = []
i = 0
while i<len(words):
llen = 0
cur = i
while i<len(words):
llen += len(words[i])
if llen>maxWidth:
llen -= len(words[i])
break
llen+=1
i+=1
llen -=1
if i != len(words):
wordcnt = i-cur
extra = maxWidth-llen
if wordcnt>1:
spaces = extra/(wordcnt-1)
r = extra%(wordcnt-1)
else:
spaces = extra
r = 0
else:
spaces = 0
r = 0
line = ""
for word in words[cur:i]:
line += word
line += " "*(spaces+1)
if r>0:
line += " "
r -= 1
line = line[:maxWidth]
if len(line)<maxWidth:
line+=" "*(maxWidth-len(line))
lines.append(line)
return lines
# Time: O(n)
# Space: O(k), k is maxWidth.
class Solution2(object):
def fullJustify(self, words, maxWidth):
"""
:type words: List[str]
:type maxWidth: int
:rtype: List[str]
"""
def addSpaces(i, spaceCnt, maxWidth, is_last):
if i < spaceCnt:
return 1 if is_last else (maxWidth // spaceCnt) + int(i < maxWidth % spaceCnt)
return 0
def connect(words, maxWidth, begin, end, length, is_last):
s = [] # The extra space O(k) is spent here.
n = end - begin
for i in range(n):
s += words[begin + i],
s += ' ' * addSpaces(i, n - 1, maxWidth - length, is_last),
# For only one word in a line.
line = "".join(s)
if len(line) < maxWidth:
line += ' ' * (maxWidth - len(line))
return line
res = []
begin, length = 0, 0
for i in range(len(words)):
if length + len(words[i]) + (i - begin) > maxWidth:
res += connect(words, maxWidth, begin, i, length, False),
begin, length = i, 0
length += len(words[i])
# Last line.
res += connect(words, maxWidth, begin, len(words), length, True),
return res
if __name__ == "__main__":
assert Solution().fullJustify(["This", "is", "an", "example", "of", "text", "justification."], 16) \
== ['This is an', 'example of text', 'justification. ']