TLE '17 Contest 4 P3 - Fax's Christmas Dish
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Fax McClad, Croneria's most meticulous bounty hunter, is going to prepare a dish for Christmas!
There are  different food items, numbered from 
 to 
. There are 
 different recipes. A recipe consists of a non-empty list of items that need to be combined to produce a target item. Only one unit of each item in the list is required, and the target item will not be in the list. Additionally, no two recipes will have the same target item, each item in the list has a greater number than the target item's number, item 
 is the target item in exactly one recipe, and items 
 to 
 appear in exactly one recipe's list.
Fax wants to have one unit of item  as his dish. He will receive 
 item on each of the next 
 days. On the 
 day, he will receive item 
.
What is the earliest day that Fax can obtain item ?
Constraints
| Subtask | Points | Additional Constraints | 
|---|---|---|
| 1 | 10 | |
| 2 | 10 | |
| 3 | 30 | |
| 4 | 50 | None | 
Input Specification
The first line will contain integers , 
, and 
.
Each of the next  lines will contain one recipe. A recipe is one line long and follows this format:
- The first integer is the target item.
 - The second integer is the number of required items.
 - The remaining integers are the required items.
 
The last line will contain  integers. The 
 integer in this line is 
.
Output Specification
If Fax cannot obtain item  after all 
 days, output 
-1. Otherwise, output the earliest day that Fax can obtain item .
Sample Input 1
7 3 8
2 2 3 6
4 2 5 7
1 2 2 4
3 3 6 3 5 4 4 1
Sample Output 1
6
Explanation for Sample Output 1
After  days, Fax has these items: 
3 3 6 3 5 4. Fax can follow the first recipe to get 2 3 3 5 4, then the third recipe to get 1 3 3 5.
Sample Input 2
4 1 7
1 3 2 3 4
2 2 3 3 2 3 3
Sample Output 2
-1
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