====== 이분 그래프 ======

===== 풀이 =====
  * 그래프가 [[ps:그래프#특수한 그래프|이분 그래프]]인지만 판별하면 되는 기본 문제. 시간복잡도는 O(V+E)

===== 코드 =====
<dkpr py>
"""Solution code for "BOJ 1707. 이분 그래프".

- Problem link: https://www.acmicpc.net/problem/1707
- Solution link: http://www.teferi.net/ps/problems/boj/1707
"""

import sys
from teflib import graph as tgraph


def main():
    K = int(sys.stdin.readline())
    for _ in range(K):
        V, E = [int(x) for x in sys.stdin.readline().split()]
        graph = tgraph.create_graph_from_input(V, E)

        try:
            tgraph.two_coloring(graph)
            print('YES')
        except ValueError:
            print('NO')


if __name__ == '__main__':
    main()
</dkpr>
  * Dependency: 
    * [[:ps:teflib:graph#create_graph_from_input|teflib.graph.create_graph_from_input]]
    * [[:ps:teflib:graph#two_coloring|teflib.graph.two_coloring]]

{{tag>BOJ ps:problems:boj:골드_4}}