Roads
The mayor decided to check Gadyukino roads just after overhaul. To do this, he wants to pass on every road in both directions.
Help the Mayor to make the shortest route that goes through each road in each direction at least once.
The city Gadyukino n and m crossings of roads, each of which connects two different intersection. Between the two junctions can be no more than one way.
It is known that the roads of each intersection can be reached any other.
Input
The input file contains integers n and m (1 ≤ n ≤ 10^4, 1 ≤ m ≤ 10^5), and then m pairs of integers a_i and b_i — numbers of corners, which connects the i-th path.
Output
Display the number of s - the minimum length of the path and then the number s+1 - perkrestkov numbers in the order in which they must pass.