import sys
sys.setrecursionlimit(999999999)


from collections import deque

n, m = map(int, input().split())
link = {}
init_node = -1
for i in range(m):
    a, b = map(int, input().split())
    init_node = a
    if a not in link:
        link[a]= []
    if b not in link:
        link[b] = []

    link[a].append(b)
    link[b].append(a)

color = [-1] * (100007)
def bfs(init_node):
    que = deque()
    que.append(init_node)
    color[init_node] = 1

    while len(que) > 0:
        cur = que.popleft()
        for ne in link[cur]:
            if color[ne] == -1:
                for next in link[ne]:
                    if color[next] == 1-color[cur]:
                        return False
                color[ne] = 1-color[cur]
                que.append(ne)

    return True

print('Yes' if bfs(init_node) else 'No')