public class tjhkzysf
{
//条件和扩展运算符
public static void main(String[] args){
int a =10;
int b =20;
a+=b;//a = a+b
a-=b;//a = a-b
System.out.println(a);
//========================================
//字符串连接符
System.out.println(a+b);//输出30
System.out.println(""+a+b);//字符串连接输出1020
System.out.println(a+b+"");//输出30,运算顺序不能错
//=========================================
//三元运算符
//x?y:z
//如果x==true 则为y。否则为z
int score =80;
String jieguo =score <60 ?“不及格”:“及格”;//此处输出及格
System.out.println(jieguo);
}
}