if_else

package myproject;

public class TestIf {
    public static void main(String[] args) {
        double d=Math.random();
        int e=(int)(d*5);
        System.out.println(e);
        
        //单选择结构
        if (e>3) {
            System.out.println("大数");
        }
        System.out.println("it is over");
        
        //双选择
        
        if (e>3) {
            System.out.println("大数");
        }else {
            System.out.println("小数");
        }
        
        System.out.println("it is over");
        
        //多选择
        
        if (e>4) {
            System.out.println("大数");
        }else if(e>3 && e<=4) {
            System.out.println("中数");
        }else {
            System.out.println("小数");
        }
        System.out.println("it is over");
    }

}