68. Text Justification

Author: Partho Biswas

README.md

@@ -529,6 +529,8 @@ BFS, DFS, Dijkstra, Floyd–Warshall, Bellman-Ford, Kruskal, Prim's, Minimum Spa
 |14| [253. Meeting Rooms II](https://tinyurl.com/r8vr7qo)| [Python](https://tinyurl.com/wu6rdaw/253_Meeting_Rooms_II.py)| [Official](https://leetcode.com/problems/meeting-rooms-ii/solution/) | Medium | Greedy and uses heap |
 |15| [759. Employee Free Time](https://tinyurl.com/y5z73vre)| [Python](https://tinyurl.com/wu6rdaw/759_Employee_Free_Time.py)| [Educative.io](https://tinyurl.com/v42vmyr) | Hard | Greedy and uses heap. Not done. Check again |
 |16| [659. Split Array into Consecutive Subsequences](https://tinyurl.com/vsbddyl) | [Python](https://tinyurl.com/wu6rdaw/659_Split_Array_into_Consecutive_Subsequences.py)| [Art 0](https://tinyurl.com/qq5jucw), [Art 1](https://tinyurl.com/qk7m78s), [Art 2](https://tinyurl.com/sjkdtre), [Art 3](https://tinyurl.com/tnewgqa), **[Vid 1](https://tinyurl.com/u2hnq84)**, **[Art 4](https://tinyurl.com/w3j4yqp)** | Medium | 📌 It's a fucking unclear problem. TODO: Not done. Check again later |
+|16| **[843. Guess the Word](https://tinyurl.com/vyk9ynp)** | [Python](https://tinyurl.com/wu6rdaw/843_Guess_the_Word.py)| --- | Hard | TODO: NOT DONE |
+|16| **[68. Text Justification](https://tinyurl.com/r7bzsul)** | [Python](https://tinyurl.com/wu6rdaw/68_Text_Justification.py)| [Vid 1](https://tinyurl.com/jkx2usg), [Vid 2](https://tinyurl.com/wd7rja2), [Vid 3](https://tinyurl.com/qlbsfqf), [Art 0](https://tinyurl.com/u5r5cuy), [Art 1](https://tinyurl.com/s84dym2) | Hard | TODO: Check again later. Very Important |
 
 </p>
 </details>

leetcode.com/python/68_Text_Justification.py

@@ -0,0 +1,51 @@
+class Solution(object):
+    def fullJustify(self, words, maxWidth):
+        """
+        :type words: List[str]
+        :type maxWidth: int
+        :rtype: List[str]
+        """
+        currentWordIdx = 0           # the index of the current word
+        ans = []
+        while currentWordIdx < len(words):
+            wordCountForEachLine = self.getWordsCountForEachLine(currentWordIdx, words, maxWidth)
+            line = self.insertSpaces(currentWordIdx, wordCountForEachLine, words, maxWidth)  # create a line which contains words from words[currentWordIdx] to words[currentWordIdx + wordCountForEachLine - 1]
+            ans.append(line)
+            currentWordIdx += wordCountForEachLine
+        return ans
+
+
+    # How many words we need to form each line;
+    def getWordsCountForEachLine(self, currentWordIdx, words, maxWidth):
+        wordCountForLine = 1       # figure out how many words can fit into a line, which starts from 1 ssince we are adding  one word initially
+        currentLen = len(words[currentWordIdx])
+        while currentWordIdx + wordCountForLine < len(words):
+            nextLen = len(words[currentWordIdx + wordCountForLine]) + 1 # here, the last added 1 is for an added space at the left
+            if currentLen + nextLen <= maxWidth:
+                wordCountForLine += 1
+                currentLen += nextLen
+            else:
+                break
+        return wordCountForLine
+
+
+
+    # How many spaces we should insert between two words.
+    def insertSpaces(self, currentWordIdx, wordCountForEachLine, words, maxWidth):
+        initialLine = ' '.join(words[currentWordIdx:currentWordIdx + wordCountForEachLine])     # Concatenate words[currentWordIdx:currentWordIdx + wordCountForEachLine] into one line
+        finalLine = ""
+        if wordCountForEachLine == 1 or currentWordIdx + wordCountForEachLine == len(words):    # if the line contains only one word or it is the last line
+            spaces = maxWidth - len(initialLine)                                                # we just need to left assigned it
+            finalLine = initialLine + ' '*spaces
+        else:
+            totalSpaces = maxWidth - len(initialLine) + (wordCountForEachLine - 1)              # total number of spaces we need insert
+            averageSpaces = totalSpaces // (wordCountForEachLine - 1)                                  # average number of spaces we should insert between two words
+            leftWords = totalSpaces % (wordCountForEachLine - 1)                           # number of 'left' words, i.e. words that have 1 more space than the other words on the right side
+            if leftWords > 0:
+                finalLine = (" "*(averageSpaces + 1)).join(words[currentWordIdx:currentWordIdx + leftWords])    # left words. The reason for +1 is, these words will have one more spaces then others
+                finalLine += " "*(averageSpaces + 1)                                        # spaces between left words & right words
+                finalLine += (" "*averageSpaces).join(words[currentWordIdx + leftWords:currentWordIdx + wordCountForEachLine])      # right words
+            else:
+                finalLine = (" "*averageSpaces).join(words[currentWordIdx:currentWordIdx + wordCountForEachLine])
+        return finalLine
+