算法实战：重新排列单词间空格的模拟解法

2024-01-03 03:28:26

算法的世界里，模拟题就像一场益智游戏，考验着我们的思维敏捷度和对细节的关注。今天，我们挑战的是 LeetCode 上的 1592. 重新排列单词间的空格。

题目简介

这是一道简单的模拟题，要求我们给定一个字符串 s，重新排列字符串中的单词，单词间仅用一个空格隔开。

模拟解法

模拟解法的精髓在于逐个字符地处理输入字符串，并根据给定的规则对字符进行操作。本题中，我们需要将单词从字符串中提取出来，然后重新排列并添加空格。

Python 代码示例

def reorderSpaces(s):
    """
    :type s: str
    :rtype: str
    """
    # 提取单词和空格
    words = s.split()
    spaces = len(s) - sum(len(word) for word in words)

    # 处理边界情况：没有单词或只有一个单词
    if not words or len(words) == 1:
        return s

    # 计算每个单词之间的空格数
    spaces_between_words = spaces // (len(words) - 1)
    extra_spaces = spaces % (len(words) - 1)

    # 重新排列单词并添加空格
    result = ""
    for word in words:
        result += word + " " * spaces_between_words

    # 添加额外的空格
    result += " " * extra_spaces

    # 去除末尾多余的空格
    return result.rstrip()

Java 代码示例

public class Solution {
    public String reorderSpaces(String s) {
        String[] words = s.split(" +");
        int spaces = s.length() - words.length;

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < words.length; i++) {
            sb.append(words[i]);
            if (i < words.length - 1) {
                int spacesBetweenWords = spaces / (words.length - 1);
                int extraSpaces = spaces % (words.length - 1);
                if (extraSpaces > 0) {
                    sb.append(' ');
                    extraSpaces--;
                }
                for (int j = 0; j < spacesBetweenWords; j++) {
                    sb.append(' ');
                }
            }
        }

        return sb.toString();
    }
}

C++ 代码示例

class Solution {
public:
    string reorderSpaces(string s) {
        vector<string> words;
        int spaces = 0;
        stringstream ss(s);
        string word;
        while (ss >> word) {
            words.push_back(word);
            spaces += count(word.begin(), word.end(), ' ');
        }

        if (words.size() == 1) {
            return s;
        }

        int spacesBetweenWords = spaces / (words.size() - 1);
        int extraSpaces = spaces % (words.size() - 1);

        string result;
        for (int i = 0; i < words.size(); i++) {
            result += words[i];
            if (i < words.size() - 1) {
                for (int j = 0; j < spacesBetweenWords; j++) {
                    result += ' ';
                }
                if (extraSpaces > 0) {
                    result += ' ';
                    extraSpaces--;
                }
            }
        }

        return result;
    }
};

JavaScript 代码示例

/**
 * @param {string} s
 * @return {string}
 */
const reorderSpaces = (s) => {
  const words = s.split(" ");
  const spaces = s.length - words.join("").length;

  if (words.length === 1) {
    return s;
  }

  const spacesBetweenWords = Math.floor(spaces / (words.length - 1));
  const extraSpaces = spaces % (words.length - 1);

  let result = "";
  for (let i = 0; i < words.length; i++) {
    result += words[i];
    if (i < words.length - 1) {
      for (let j = 0; j < spacesBetweenWords; j++) {
        result += " ";
      }
      if (extraSpaces > 0) {
        result += " ";
        extraSpaces--;
      }
    }
  }

  return result.trim();
};