Preparando MOJI

Shortest Path

3000ms 262144K

Description:

In Ancient Berland there were n cities and m two-way roads of equal length. The cities are numbered with integers from 1 to n inclusively. According to an ancient superstition, if a traveller visits three cities ai, bi, ci in row, without visiting other cities between them, a great disaster awaits him. Overall there are k such city triplets. Each triplet is ordered, which means that, for example, you are allowed to visit the cities in the following order: ai, ci, bi. Vasya wants to get from the city 1 to the city n and not fulfil the superstition. Find out which minimal number of roads he should take. Also you are required to find one of his possible path routes.

Input:

The first line contains three integers n, m, k (2 ≤ n ≤ 3000, 1 ≤ m ≤ 20000, 0 ≤ k ≤ 105) which are the number of cities, the number of roads and the number of the forbidden triplets correspondingly.

Then follow m lines each containing two integers xi, yi (1 ≤ xi, yi ≤ n) which are the road descriptions. The road is described by the numbers of the cities it joins. No road joins a city with itself, there cannot be more than one road between a pair of cities.

Then follow k lines each containing three integers ai, bi, ci (1 ≤ ai, bi, ci ≤ n) which are the forbidden triplets. Each ordered triplet is listed mo more than one time. All three cities in each triplet are distinct.

City n can be unreachable from city 1 by roads.

Output:

If there are no path from 1 to n print -1. Otherwise on the first line print the number of roads d along the shortest path from the city 1 to the city n. On the second line print d + 1 numbers — any of the possible shortest paths for Vasya. The path should start in the city 1 and end in the city n.

Sample Input:

4 4 1
1 2
2 3
3 4
1 3
1 4 3

Sample Output:

2
1 3 4

Sample Input:

3 1 0
1 2

Sample Output:

-1

Sample Input:

4 4 2
1 2
2 3
3 4
1 3
1 2 3
1 3 4

Sample Output:

4
1 3 2 3 4

Informação

Codeforces

Provedor Codeforces

Código CF59E

Tags

graphsshortest paths

Submetido 0

BOUA! 0

Taxa de BOUA's 0%

Datas 09/05/2023 08:29:35

Relacionados

Nada ainda