标签：LeetCode、贪心算法、字符串处理、文本对齐、Python、面试高频、困难题难度：困难｜核心考点：贪心策略、空格均匀分配、边界情况处理一、题目原题解读1.1 题目描述给定一个单词数组words和一个指定长度maxWidth，需要重新排版单词，生成符合要求的格式化文本，核心规则如下：每行恰好占maxWidth个字符，不多不少采用贪心算法放置单词：每行尽可能多放单词，放不下则换行单词间用空格填充，空格需尽可能均匀分配；若无法均分，左侧空格数多于右侧文本最后一行特殊处理：左对齐，单词间仅一个空格，剩余空格全部补在末尾若某一行只有一个单词：该单词左对齐，剩余空格全部补在右侧核心定义单词：由非空格字符组成的序列，长度大于0且不超过maxWidth输入保证：单词数组至少含一个单词，无需处理空输入1.2 示例演示（3组核心案例）示例1输入: words = ["This", "is", "an", "example", "of", "text", "justification."], maxWidth = 16 输出: [ "This is an", "example of text", "justification. " ]示例2输入:words = ["What","must","be","acknowledgment","shall","be"], maxWidth = 16 输出: [ "What must be", "acknowledgment ", "shall be " ] 解释: 最后一行左对齐，仅单词间一个空格，剩余空格补末尾；单行单词直接右补空格示例3输入:words = ["Science","is","what","we","understand","well","enough","to","explain","to","a","computer.","Art","is","everything","else","we","do"], maxWidth = 20 输出: [ "Science is what we", "understand well", "enough to explain to", "a computer. Art is", "everything else we", "do " ]1.3 关键约束与提示单词数量：1 ≤ words.length ≤ 300单个单词长度：1 ≤ words[i].length ≤ 20最大宽度：1 ≤ maxWidth ≤ 100，且单个单词长度≤maxWidth字符组成：小写英文字母+符号，无空格二、解题思路：贪心算法核心逻辑2.1 贪心策略拆解本题的贪心核心是**“行优先填满”**，每一步都选择当前能放下的最多单词，不考虑后续行，最大化每行单词数量，减少总行数，同时严格遵循空格分配规则，整体分为三大步骤：分组：遍历单词，按贪心规则将单词分成多行，确定每行包含哪些单词分情况处理：区分普通行（非最后一行、多行单词）、单行单词行、最后一行，分别计算空格拼接成行：按空格规则拼接单词，补满maxWidth长度，加入结果列表2.2 关键规则细化（必懂）情况1：普通行（非最后一行，含≥2个单词）计算总空格数：total_spaces = maxWidth - 该行所有单词总长度单词间间隔数：gap_num = 单词数量 - 1基础空格数：base_spaces = total_spaces // gap_num多余空格数：extra_spaces = total_spaces % gap_num（前extra_spaces个间隔，各多1个空格）情况2：单行单词行（任意位置，仅1个单词）单词左对齐，右侧直接补满空格，直至长度为maxWidth情况3：最后一行（无论单词数量）单词间仅一个空格，整体左对齐，剩余空格全部补在末尾，不做均分处理