C语言，小学生算术测试，1到100随机数，随机加减乘除，可验证ID号是否合理，给出正确和错误的题数，记录时间-test system for Pupil

设随机给出1-100中的四个数(可重复),能用加,减,乘,除,括号,给出运算结果为24的所有表达式。-Given a random set of four numbers 1-100 (repeatable), can add, subtract, multiply, divide, brackets, operation results are given for all the expressions (24).