Codeforces Round 295 (Div. 1) |
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Finished |
You are organizing a cycling race on the streets of the city. The city contains n junctions, some pairs of them are connected by roads; on each road you can move in any direction. No two roads connect the same pair of intersections, and no road connects the intersection with itself.
You want the race to be open to both professional athletes and beginner cyclists, and that's why you will organize the race in three nominations: easy, moderate and difficult; each participant will choose the more suitable nomination. For each nomination you must choose the route — the chain of junctions, consecutively connected by roads. Routes must meet the following conditions:
Preparing for the competition is about to begin, and you need to determine the routes of the race as quickly as possible. The length of the routes is not important, it is only important that all the given requirements were met.
The first line contains two integers n and m (1 ≤ n, m ≤ 2·105) — the number of intersections and roads, respectively.
The following m lines contain two integers — the numbers of the intersections connected by a road (the intersections are numbered starting with 1). It is guaranteed that each pair of intersections is connected by no more than one road, and no road connects the intersection to itself.
Please note that it is not guaranteed that you can get from any junction to any other one by using the roads.
If it is possible to create the routes, in the first line print "YES". In the next three lines print the descriptions of each of the three routes in the format "l p1 ... pl", where l is the number of intersections in the route, and p1, ..., pl are their numbers in the order they follow. The routes must meet all the requirements specified in the statement.
If it is impossible to make the routes in accordance with the requirements, print NO.
4 4
1 2
2 3
3 4
4 1
NO
5 6
1 2
1 3
1 4
2 5
3 5
4 5
YES
3 5 4 1
3 5 3 1
3 5 2 1
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