def dfs(v, c, p):
    ret = True
    color[v] = c
    for nv in G[v]:
        if nv==p:
            continue
        if color[nv]==c:
            return False
        if color[nv]==1-c:
            continue
        ret = dfs(nv, 1-c, v)
        if ret==False:
            return ret
    return ret

import sys
input = sys.stdin.readline
N, M = map(int, input().split())
AB = [list(map(int, input().split())) for _ in range(M)]
G = [[] for _ in range(N)]
for a, b in AB:
    a-=1
    b-=1
    G[a].append(b)
    G[b].append(a)
color = [-1 for _ in range(N)]
for i in range(N):
    if color[i]!=-1:
        continue
    ret = dfs(i, 0, -1)
    if ret==False:
        print("No")
        exit()
print("Yes")