Transport nodes
The country N-arity contains cities. Some of them are connected by roads, the country contains roads. From some cities goes only one way, but some cities are real transportation hubs — a lot of roads connects them with other cities. In this problem the city is a transportation hub, if it is connected with at least roads.
The description of the road network in N-arity is given. Find all its transportation hubs.
Input
The first line contains the number and the number of roads. Each of the following lines describe one way and contains two numbers and — the number of cities connected by roads. The last line of input contains an integer .
Each road is mentioned in the input no more than once.
Output
In the first line print the number of transportation hubs. In the second line print the hub numbers in ascending order.