1 遞歸

    /*** 遞歸：十進制轉二進制* @param decimal 待轉換的十進制數* @param binary  轉換后的二進制數*/public static void decimalToBinaryByRecursion(int decimal,StringBuilder binary){if(decimal <= 0){return;}decimalToBinaryByRecursion(decimal/2,binary);binary.append(decimal % 2);}

2 循環

    /*** 循環：十進制轉二進制* @param decimal 十進制數* @return 轉換后的二進制數*/public static String decimalToBinaryByCirculate(int decimal){String binary="";while (decimal > 0){int temp=decimal%2;binary=temp+binary;decimal=decimal/2;}return binary;}

3 位運算

    /*** 位運算：十進制轉二進制* @param decimal 十進制數* @return 轉換后的二進制數*/public static String decimalToBinaryByBitwise(int decimal){StringBuilder binary = new StringBuilder();while (decimal > 0) {binary.append(decimal & 1);decimal >>>= 1;}return binary.reverse().toString();}

4 測試程序

    public static void main(String[] args) {int decimalData=25;StringBuilder binary=new StringBuilder();decimalToBinaryByRecursion(decimalData,binary);System.out.print("遞歸:");System.out.println(binary);System.out.print("循環:");System.out.println(decimalToBinaryByCirculate(decimalData));System.out.print("位運算:");System.out.println(decimalToBinaryByBitwise(decimalData));}

5 運行結果