Linux bash初学-case语句

编写一个简单的bash脚本hello.sh，提供如下特性：

1. 当运行./hello.sh student , 输出为 teacher

2. 当运行./hello.sh teacher, 输出为 student

3. 当没有任何参数，或参数不是teache 或者 student 时，在控制台打印输出如下信息：

./hello.sh student | teacher

#!/bin/bash
case $1 in
    teacher)
        echo "student"
    ;;
    student)
        echo "teacher"
    ;;
    *)
        echo "./hello.sh student | teacher"
    ;;
esac

xiejiaohui-2:~ xiejiaohui$ vim hello.sh 

xiejiaohui-2:~ xiejiaohui$ ./hello.sh

./hello.sh teacher | student

xiejiaohui-2:~ xiejiaohui$ ./hello.sh student

teacher

xiejiaohui-2:~ xiejiaohui$ ./hello.sh teacher

student

xiejiaohui-2:~ xiejiaohui$