This problem is in Contest(s) below:
Contest 1054:CIE-C1-专题训练2
Contest 1024:1.3C++编程基础之算术表达式与顺序执行(20题)
Contest 1005:1.3编程基础之算术表达式与顺序执行(20题)
Contest 1017:python选择语句和运算题库