Bubble Cup V8 B Bribes
View as PDFRuritania is a country with a very badly maintained road network, which is not exactly good news for lorry drivers that constantly have to do deliveries. In fact, when roads are maintained, they become one-way. It turns out that it is sometimes impossible to get from one town to another in a legal way – however, we know all towns are reachable, though illegally!
Fortunately for us, the police tend to be very corrupt and they will allow a lorry driver to break the rules and drive in the wrong direction provided they receive 'a small gift'. There is one patrol car for every road and they will request 1000 Ruritanian dinars when a driver drives in the wrong direction. However, being greedy, every time a patrol car notices the same driver breaking the rule, they will charge double the amount of money they requested the previous time on that particular road.
Borna is a lorry driver that managed to figure out this bribing pattern. As part of his job, he has to make  stops in some towns all over Ruritania and he has to make these stops in a certain order. There are 
 towns (enumerated from 
 to 
) in Ruritania and Borna's initial location is the capital city i.e. town 
. He happens to know which ones out of the 
 roads in Ruritania are currently unidirectional, but he is unable to compute the least amount of money he needs to prepare for bribing the police. Help Borna by providing him with an answer and you will be richly rewarded.
Input Specification
The first line contains , the number of towns in Ruritania. The following 
 lines contain information regarding individual roads between towns. A road is represented by a tuple of integers 
, which are separated with a single whitespace character. The numbers 
 and 
 represent the cities connected by this particular road, and 
 is either 
 or 
: 
 means that the road is bidirectional, 
 means that only the 
 direction is legal. The next line contains 
, the number of stops Borna has to make. The final line of input contains 
 positive integers 
: the towns Borna has to visit.
Output Specification
The output should contain a single number: the least amount of thousands of Ruritanian dinars Borna should allocate for bribes, modulo .
Constraints
for all roads
for all roads
for all
Sample Input
5
1 2 0
2 3 0
5 1 1
3 4 1
5
5 4 5 2 2
Sample Output
4
Explanation
Borna first takes the route  and has to pay 1000 dinars. After that, he takes the route 
 and pays nothing this time. However, when he has to return via 
, he needs to prepare 
 
 dinars. Afterwards, getting to 
 via 
 will cost him nothing. Finally, he doesn't even have to leave town 
 to get to 
, so there is no need to prepare any additional bribe money. Hence he has to prepare 
 dinars in total.
Comments
How about Borna not richly rewarding me but instead take all that money to drive wherever he wants and richly rewards the police
This country sucks a lot. When is America gonna come and give it "freedom"?