This problem is in Contest(s) below:
Contest 1381:信管1701-02高级语言程序设计作业(2)
Contest 1382:工管1701高级语言程序设计作业(2)
Contest 1332:通工1607-09 C语言作业(2)
Contest 1333:通工1610-11 C语言作业(2)