说明： 计算练习:要求使用者输入每组运算的题量和出现数字的最大值,然后计算出随机出的计算题.电脑最后给出正确率. (Calculation exercises: ask the user to input the amount of each operation and the emergence of problems the maximum number, and then calculate the random out of the math. Finally, the accuracy of the computer.)
