1 输入10个数，求这组数据中的最小数。
2 输入一组学生某门课程的成绩，直到输入的数字为0为止。求总分以及平均分
3 输入一组字符，判断字母，数字，其他字符的个数
4 输入一个数，判断该数是否为素数。(Write a program to help you balance your checkbook.
1) Enter each withdraw (use minus sign) and deposit;
2) Signal the end with a 0 value;
3) If the user enters a withdraw cash that exceeds the current balance, the program will prompt a message and deduct the service charge.)