PROGRAMMING:"Seven Bridges problem" in Konigsberg

Konigsberg is a city on the plege river. It contains two islands and seven bridges connecting them, as shown in the figure below.
Can you walk through seven bridges like this, and each bridge only goes through once? The Swiss mathematician Leonhard Euler (1707-1783) finally solved this problem and founded topology.
This problem can now be described as the problem of judging whether the Euler circuit exists or not. Eulerian loop is a loop that can be drawn only once through each edge of the graph without leaving the pen on the paper, and can return to the starting point. Now, given an undirected graph, is there an Euler loop?
###Input format:
Enter the first line to give two positive integers, which are node number $$n $$($$1 / Le n / Le 1000 $$) and edge number $$M $$; The following $$M $$rows correspond to $$M $$edges. Each row gives a pair of positive integers, which are the numbers of the two nodes directly connected by the edge (nodes from 1 to $$n $).
###Output format:
If Euler loop exists, output 1, otherwise output 0.
###Input sample 1:
```in
6 10
1 2
2 3
3 1
4 5
5 6
6 4
1 4
1 6
3 4
3 6
```
###Output sample 1:
```out
one
```
###Input sample 2:
```
5 8
1 2
1 3
2 3
2 4
2 5
5 3
5 4
3 4
```
###Output sample 2:
```
0
```






answer：If there is no answer, please comment