[Java基础]《位运算》和《“余数符号”和“被除数符号”相同的规则》
/** * 复习位运算 * “余数符号”和“被除数符号”相同的规则 */public class WeiYunSuan { public static void main(String[] args) { //验证“余数符号”和“被除数符号”相同的规则 System.out.println((-7) / (2));//-3 System.out.println((-7) % (2));//-1 System.out.println((7) / (-2));//-3 System.out.println((7) % (-2));//1 System.out.println((-7) / (-2));//3 System.out.println((-7) % (-2));//-1 System.out.println((7) / (2));//3 System.out.println((7) % (2));//1 //对于右移(不溢出则正确，相当于乘2；溢出则不正确) //不溢出的情况下，左移和乘2均正确 System.out.println(33 << 1);//66 System.out.println(33 *2);//66 System.out.println(-33 << 1);//-66 System.out.println(-33 *2);//-66 //溢出的情况下，左移和乘2均不正确 int num = -1-(1<<30);//1011 1111 1111 1111 System.out.println(num);//-1073741825 System.out.println(num << 1);//2147483646 System.out.println(num *2);//2147483646 num = (1<<31)-1;//0111 1111 1111 1111 System.out.println(num);//2147483647 System.out.println(num << 1);//-2 System.out.println(num *2);//-2 //对于带符号右移(无论正数负数均正确，相当于除2) System.out.println(33 >> 1);//16 System.out.println(33 / 2);//16 System.out.println((-33) >> 1);//-17 这里不同? System.out.println((-33) / 2);//-16 System.out.println((-1) >> 1);//-1 这里不同 ? ? ? ? System.out.println((-1) / 2);//0? ? ? ? System.out.println((-4) >> 1);//-1 System.out.println((-3) >> 1);//-2 System.out.println((-3) / 2);//-1 //对于无符号右移(正数与除2相同，负数则不正确) System.out.println(33 >>> 1);//16 System.out.println(33 / 2);//16 System.out.println((-33) >>> 1);//2147483631 System.out.println((-33) / 2);//-16 System.out.println((-1) >>> 1);//2147483647 System.out.println((-1) / 2);//0 }}