&和&&的作用和區別

&

• 邏輯與，& 兩邊的表達式都會進行運算
• 整數的位運算符

 

&&

• 短路與，&& 左邊的表達式結果為 false 時，&& 右邊的表達式不參與計算

package constxiong.interview;

/**
 * 測試 & &&
 * @author ConstXiong
 */
public class TestAnd {

    public static void main(String[] args) {
        int x = 10;
        int y = 9;
        if (x == 9 & ++y > 9) {
        }
        System.out.println("x = " + x + ", y = " + y);
        
        int a = 10;
        int b = 9;
        if (a == 9 && ++b > 9) {//a == 9 為 false，所以 ++b 不會運算，b=9
        }
        System.out.println("a = " + a + ", b = " + b);
        
        //00000000000000000000000000000001
        //00000000000000000000000000000010
        //=
        //00000000000000000000000000000000
        System.out.println(1 & 2);//打印0
    }
    
}

 

打印

x = 10, y = 10
a = 10, b = 9
0

 

  

  

來一道刷了進BAT的面試題？