# Kotlin 程序：將八進制數轉換為十進制，反之亦然 > 原文： [https://www.programiz.com/kotlin-programming/examples/octal-decimal-convert](https://www.programiz.com/kotlin-programming/examples/octal-decimal-convert) #### 在此程序中，您將學習使用 Kotlin 中的函數將八進制數轉換為十進制數，反之亦然。 ## 示例 1：將十進制轉換為八進制的程序 ```kt fun main(args: Array<String>) { val decimal = 78 val octal = convertDecimalToOctal(decimal) println("$decimal in decimal = $octal in octal") } fun convertDecimalToOctal(decimal: Int): Int { var decimal = decimal var octalNumber = 0 var i = 1 while (decimal != 0) { octalNumber += decimal % 8 * i decimal /= 8 i *= 10 } return octalNumber } ``` 運行該程序時，輸出為： ```kt 78 in decimal = 116 in octal ``` 此轉換發生為： ```kt 8 | 78 8 | 9 -- 6 8 | 1 -- 1 8 | 0 -- 1 (116) ``` * * * ## 示例 2：將八進制轉換為十進制的程序 ```kt fun main(args: Array<String>) { val octal = 116 val decimal = convertOctalToDecimal(octal) println("$octal in octal = $decimal in decimal") } fun convertOctalToDecimal(octal: Int): Int { var octal = octal var decimalNumber = 0 var i = 0 while (octal != 0) { decimalNumber += (octal % 10 * Math.pow(8.0, i.toDouble())).toInt() ++i octal /= 10 } return decimalNumber } ``` 運行該程序時，輸出為： ```kt 116 in octal = 78 in decimal ``` This conversion takes place as: ```kt 1 * 82 + 1 * 81 + 6 * 80 = 78 ``` 以下是等效的 Java 代碼： [Java 程序：將八進制轉換為十進制，反之亦然](/java-programming/examples/octal-decimal-convert "How to convert octal to decimal and vice-versa in Java?")