CSES - Shortest Routes II
  • Time limit: 1.00 s
  • Memory limit: 512 MB

There are n cities and m roads between them. Your task is to process q queries where you have to determine the length of the shortest route between two given cities.

Input

The first input line has three integers n, m and q: the number of cities, roads, and queries.

Then, there are m lines describing the roads. Each line has three integers a, b and c: there is a road between cities a and b whose length is c. All roads are two-way roads.

Finally, there are q lines describing the queries. Each line has two integers a and b: determine the length of the shortest route between cities a and b.

Output

Print the length of the shortest route for each query. If there is no route, print -1 instead.

Constraints

  • 1 \le n \le 500
  • 1 \le m \le n^2
  • 1 \le q \le 10^5
  • 1 \le a,b \le n
  • 1 \le c \le 10^9

Example

Input:

4 3 5
1 2 5
1 3 9
2 3 3
1 2
2 1
1 3
1 4
3 2

Output:

5
5
8
-1
3