shunfurh 于 2017.09.13 10:29 提问
- The Final Countdown
When Doctor Doom modeled LAI-BACH (the Latverian Aerospace Institute, Bolograd Active Control Headquarters) on Mission Command with
NASA, he perhaps cribbed from the source a bit too closely.
NASA (and therefore LAI-BACH) have a peculiar way of handling countdowns to missions. While the clock may state that it is, say, thirty minutes
until liftoff for a rocket or shuttle, there are built-in holds where the clock is stopped for a set amount of time. For example, there may be a 15-minute
hold when the countdown reaches the 8-minute mark. The end result is that more time passes from the beginning of the countdown to the end than
the numbers on the clock would imply.
LAI-BACH uses a simple "command file" format to manage holds for their countdowns on their computer systems. All commands start with a
positive integer no greater than 1440 (countdowns longer than a day make Doctor Doom angry), followed by a directive. The format of the
commands is as follows:
All conditions are represented by short strings of lowercase letters, no more than 20 characters long; their actual values are not provided in the
command structure, as they are determined by actual conditions during the launch (whether the fuel tanks have been topped off, whether the
Fantastic Four is currently fighting Doctor Doom, and so on), but they are always either true or false and do not change during the course of a single
countdown. A hold time n is a positive integer no more than 60 (minutes), as long delays also irritate Victor.
Given a particular command file, you are to determine both the shortest possible time and the longest possible time that the countdown can run. The
commands may be present in any order, but there will always be one and only one START directive; there will be precisely as much whitespace on
each line as dictated by the format given above. No two commands in a command file will reference the same minute t.
Input to this problem will begin with a line containing a single integer N (1 ≤ N ≤ 100) indicating the number of data sets. Each data set consists of
the following components:
A line containing a single integer L (1 ≤ L ≤ 100) indicating the number of lines in the particular "command file"; and
A series of L lines representing the command file, in the format described above.
For each data set, print "min TO max", where min is the shortest possible time the countdown can last in minutes, and max is the longest possible
time the countdown can last in minutes.
15 HOLD 5
10 HOLD 5 IF fantasticfour
75 HOLD 20 IF yellowlightblinks
150 HOLD 30 IF NOT fueled
35 TO 40
300 TO 350
- caozhy 2017.09.29 23:55