class Person{
    public static void main(String[] args){
        int age = 10;
        if(age>10){
            System.out.println("年龄太大");
        }
        else if(age>20){
            System.out.println("123");
        }
        else{
            age = 18;
        }
        for(int i =0;i<12;i++){
            age = 19;
            System.out.println("234");
            System.out.println("456");
        }
        char i = 'a';
        switch(i) {
            case 'a':
                System.out.println("123");
                break;
            case 'b':
                System.out.println("456");
                break;
        }
    }
}