N, M = map(int, input().split())
G = [[] for i in range(N)]
for i in range(M):
    u, v = map(int, input().split())
    u, v = u - 1, v - 1
    G[u].append(v)
    G[v].append(u)
    
dist = [-1] * N
from collections import deque
def bfs(G, s):
    Q = deque([s])
    N = len(G)
    par = [-1] * N
    dist[s] = 0
    while Q:
        u = Q.popleft()
        for v in G[u]:
            if dist[v] != -1:
                if dist[v] == dist[u]:
                    print("No")
                    exit()
                continue
            dist[v] = 1 - dist[u]
            par[v] = u
            Q.append(v)
    return dist

for i in range(N):
    if dist[i] != -1:
        continue
    bfs(G, i)
    
print("Yes")