Java算法：二进制和位运算

来源：左程云算法

public class Main {
    public static void main(String[] args) {
      int a=78;
        System.out.println(a);
        printBinary(a);
        System.out.println("----a-----");
        //负数
        int b=-6;
        System.out.println(b);
        printBinary(b);
        System.out.println("----b-----");
        //二进制形式定义变量
        int c=0b1001110;
        System.out.println(c);
        printBinary(c);
        System.out.println("----c-----");
        //十六进制形式定义变量
        int d=0x4e;
        System.out.println(d);
        printBinary(d);
        System.out.println("----d-----");
        //~   相反数
        System.out.println(a);
        printBinary(a);
        printBinary(~a);
        int e=~a+1;
        System.out.println(e);
        printBinary(e);
        System.out.println("---e----");
        //int long的最小值，取相反数绝对值都是自己
        int f=Integer.MIN_VALUE;
        System.out.println(f);
        printBinary(f);
        System.out.println(-f);
        printBinary(-f);
        System.out.println(~f+1);
        printBinary(~f+1);
        System.out.println("----f----");
        //|  &   ^
        int g=0b0001010;
        int h=0b0001100;
        printBinary(g|h);
        printBinary(g&h);
        printBinary(g^h);
        System.out.println("----g,h----");
        //
        System.out.println("test1测试开始");
        boolean test1=returntrue()|returnfalse();
        System.out.println("test1结果："+test1);
        System.out.println("test2测试开始");
        boolean test2=returntrue()||returnfalse();
        System.out.println("test2结果："+test2);
        System.out.println("test3测试开始");
        boolean  test3=returnfalse()&returntrue();
        System.out.println("test3结果："+test3);
        System.out.println("test4测试开始");
        boolean test4=returnfalse()&&returntrue();
        System.out.println("test4结果："+test4);
        System.out.println("----|,||,&,&&-----");
        //<<
        int i=0b0011010;
        printBinary(i);
        printBinary(i<<1);
        printBinary(i<<2);
        printBinary(i<<3);
        System.out.println("---i<<----");
        //  非负数 >>  >>>效果一样
        printBinary(i);
        printBinary(i>>2);
        printBinary(i>>>2);
        //负数  >>  >>>效果不一样
        int j=0b11110000000000000000000000000000;
        printBinary(j);
        printBinary(j>>2);
        printBinary(j>>>2);
        System.out.println("----j>>  >>>----");
        //
        int k=10;
        System.out.println(k);
        System.out.println(k << 1);
        System.out.println(k << 2);
        System.out.println(k << 3);
        System.out.println(k >> 1);
        System.out.println(k >> 2);
        System.out.println(k >> 3);
        System.out.println("===k===");


    }
    public  static  boolean returntrue()
    {
        System.out.println("进入了returnTrue函数");
        return true;
    }
    public  static boolean returnfalse()
    {
        System.out.println("进入了returnfalse函数");
        return false;
    }
    public  static void printBinary(int num)
    {
        //打印int类型的数字，32位状态
        for(int i=31;i>=0;i--)
        {
            System.out.print((num&(1<<i))==0?"0":'1');
        }
        System.out.println();
    }
}