import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes")
no = lambda :print("no");No = lambda :print("No")
#######################################################################

n, m = na()
g = [[] for i in range(n)]
for i in range(m):
    a, b = na()
    g[a-1].append(b-1)
    g[b-1].append(a-1)

def is_bipartite(g):
    n = len(g)
    color = [-1] * n
    for i in range(n):
        if color[i] == -1:
            stack = [i]
            color[i] = 0
            while stack:
                v = stack.pop()
                for u in g[v]:
                    if color[u] == -1:
                        color[u] = color[v] ^ 1
                        stack.append(u)
                    elif color[u] == color[v]:
                        return False
    return True

if is_bipartite(g):
    print("Yes")
else:
    print("No")