One of the reasons why Jeffrey is so scared of roads is that Frank is able to drive on them. Frank is not a very talented driver; in fact, he is one of the worst. However, Frank believes that he won't cause any accidents if the distance he drives is under kilometres.
Today, Frank needs to buy some apples. From his house, he plans to drive his car on the roads that Jeffrey is scared of in order to get to a Food Basics. To ensure that Frank doesn't cause any accidents, Frank will only visit a Food Basics that is under kilometres from his house. Help Frank find all of the Food Basics that he can visit.
The first line of input will contain four integers, , the number of kilometres that Frank can drive without seriously injuring someone, , the number of buildings that Frank can visit, , the number of roads that Frank can drive on, and , the number of Food Basics near Frank's house.
The next lines will contain an integer , denoting the buildings that are a Food Basics. Frank's house will never be a Food Basics. Who would want to live in a grocery store?
We define a road as a connection from one building to another. Each building is marked with a number from to . Frank's house will be denoted by the integer . The next lines will be in the form
A B L, denoting a road that travels from building to building of length kilometres. The road can only be traveled in one direction.
Output the number of Food Basics that Frank can visit, within kilometres from his house.
15 3 5 2 2 3 0 1 2 1 2 10 1 3 20 0 3 22 0 2 15
Shortest distance from Frank's house to building 2 is 12. Shortest distance from Frank's house to building 3 is 22. The only Food Basics reachable from Frank's house is building 2.