设计一个以文件方式存储事件结点网络（例如图7.31所示）的格式，从而实现从一个文件中读入一个事件结点网络，并求出各活动的可能的最早开始时间和允许的最晚完成时间、整个工程的最短完成时间、哪些活动是关键活动、提高哪些活动的速度能够使整个工程提前完成等等，并将求出的结果写入到另一个文件。-Design of a file stored event node network (for example, as shown in Figure 7.31) format, in order to achieve a file read from an event node network, and calculate the activities of the earliest possible start time and allow the latest completion time, the shortest project completion time, which activities are the key activities to enhance the speed of which activities can make the whole project completed ahead of schedule, etc., and the results obtained written to another file.