# Kotlin 程序：按字典順序對元素進行排序 > 原文： [https://www.programiz.com/kotlin-programming/examples/lexicographical-order-words](https://www.programiz.com/kotlin-programming/examples/lexicographical-order-words) #### 在此程序中，您將學習使用`for`循環和 Kotlin 中的`if`循環按字典順序對元素詞進行排序。 ## 示例：按字典順序對字符串排序的程序 ```kt fun main(args: Array<String>) { val words = arrayOf("Ruby", "C", "Python", "Java") for (i in 0..2) { for (j in i + 1..3) { if (words[i].compareTo(words[j]) > 0) { // swap words[i] with words[j[ val temp = words[i] words[i] = words[j] words[j] = temp } } } println("In lexicographical order:") for (i in 0..3) { println(words[i]) } } ``` 運行該程序時，輸出為： ```kt In lexicographical order: C Java Python Ruby ``` 在上述程序中，要排序的 5 個單詞的列表存儲在變量`word`中。 然后，我們遍歷每個單詞（`words[i]`），并將其與數組中之后的所有單詞（`words[j]`）進行比較。 這是通過使用字符串的`compareTo()`方法完成的。 如果`compareTo()`的返回值大于 0，則必須在位置上進行交換，即`word[i]`在`word[j]`之后。 因此，在每次迭代中，`words[i]`包含最早的單詞。 執行步驟 | 迭代 | 初始單詞 | `i` | `j` | `words[]` | | --- | --- | --- | --- | --- | | 1 | `{ "Ruby", "C", "Python", "Java" }` | 0 | 1 | `{ "C",?"Ruby", "Python", "Java" }` | | 2 | `{ "C",?"Ruby", "Python", "Java" }` | 0 | 2 | `{ "C",?"Ruby", "Python", "Java" }` | | 3 | `{ "C",?"Ruby", "Python", "Java" }` | 0 | 3 | `{ "C",?"Ruby", "Python", "Java" }` | | 4 | `{ "C",?"Ruby", "Python", "Java" }` | 1 | 2 | `{ "C", "Python",?"Ruby", "Java" }` | | 5 | `{ "C", "Python",?"Ruby", "Java" }` | 1 | 3 | `{ "C", "Java",?"Ruby", "Python" }` | | 最后 | `{ "C", "Java",?"Ruby", "Python" }` | 2 | 3 | `{ "C", "Java", "Python",?"Ruby" }` | 以下是等效的 Java 代碼：[以字典順序對單詞進行排序的 Java 程序](/java-programming/examples/lexicographical-order-words "Java program to sort words in lexicographical order")