feat: text-justification-dp challenge

Author: IbatoLionDev

3-HARD/Python/9-text-justification-dp/proposed-solution/__pycache__/text_justifier.cpython-312.pyc

@@ -0,0 +1,16 @@
+# Challenge: Given a set of words and a maximum width, implement a dynamic programming algorithm
+# to justify text optimally, minimizing penalties for irregular spaces.
+# Use object-oriented programming and follow the DRY principle.
+
+from text_justifier import TextJustifier
+
+def main():
+    words = ["This", "is", "an", "example", "of", "text", "justification."]
+    max_width = 16
+    justifier = TextJustifier(words, max_width)
+    justified_text = justifier.justify()
+    for line in justified_text:
+        print(f'"{line}"')
+
+if __name__ == "__main__":
+    main()

3-HARD/Python/9-text-justification-dp/proposed-solution/main.py

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+from typing import List
+
+class TextJustifier:
+    def __init__(self, words: List[str], max_width: int):
+        self.words = words
+        self.max_width = max_width
+        self.n = len(words)
+        self.dp = [float('inf')] * (self.n + 1)
+        self.dp[self.n] = 0
+        self.breaks = [-1] * (self.n + 1)
+
+    def _cost(self, i: int, j: int) -> float:
+        length = sum(len(self.words[k]) for k in range(i, j + 1)) + (j - i)
+        if length > self.max_width:
+            return float('inf')
+        return (self.max_width - length) ** 3
+
+    def justify(self) -> List[str]:
+        for i in range(self.n - 1, -1, -1):
+            for j in range(i, self.n):
+                cost = self._cost(i, j)
+                if cost == float('inf'):
+                    break
+                if self.dp[j + 1] + cost < self.dp[i]:
+                    self.dp[i] = self.dp[j + 1] + cost
+                    self.breaks[i] = j
+
+        lines = []
+        i = 0
+        while i < self.n:
+            j = self.breaks[i]
+            line_words = self.words[i:j + 1]
+            line = self._justify_line(line_words)
+            lines.append(line)
+            i = j + 1
+        return lines
+
+    def _justify_line(self, line_words: List[str]) -> str:
+        if len(line_words) == 1:
+            return line_words[0] + ' ' * (self.max_width - len(line_words[0]))
+
+        total_spaces = self.max_width - sum(len(word) for word in line_words)
+        spaces_between_words = len(line_words) - 1
+        space, extra = divmod(total_spaces, spaces_between_words)
+
+        line = ''
+        for i, word in enumerate(line_words[:-1]):
+            line += word + ' ' * (space + (1 if i < extra else 0))
+        line += line_words[-1]
+        return line