N, M = list(map(int, input().split()))



class UnionFind():

    def __init__(self, n):

        self.n = n

        self.parents = [-1] * n



    def find(self, x):

        if self.parents[x] < 0:

            return x

        else:

            self.parents[x] = self.find(self.parents[x])

            return self.parents[x]



    def union(self, x, y):

        x = self.find(x)

        y = self.find(y)

        if x == y:

            return

        if self.parents[x] > self.parents[y]:

            x, y = y, x

        self.parents[x] += self.parents[y]

        self.parents[y] = x



    def size(self, x):

        return -self.parents[self.find(x)]



    def same(self, x, y):

        return self.find(x) == self.find(y)



    def members(self, x):

        root = self.find(x)

        return [i for i in range(self.n) if self.find(i) == root]



    def roots(self):

        return [i for i, x in enumerate(self.parents) if x < 0]



    def group_count(self):

        return len(self.roots())



    def all_group_members(self):

        return {r: self.members(r) for r in self.roots()}



    def __str__(self):

        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots())



uf = UnionFind(N)

for _ in range(M):

    a, b = [int(x)-1 for x in input().split()]

    uf.union(a, b)



ans = 0

for i in range(N):

    ans = max(ans, uf.size(i))

print(ans)



import sys

sys.setrecursionlimit(10 ** 9)



N, M = list(map(int, input().split()))



root = [-1] * N





def r(x):

    if root[x] < 0:

        return x

    else:

        root[x] = r(root[x])

        return root[x]





def unite(x, y):

    x = r(x)

    y = r(y)

    if x == y:

        return

    

    root[x] += root[y]

    root[y] = x





def size(x):

    return -r(x)





for i in range(M):

    a, b = list(map(int, input().split()))

    a -= 1

    b -= 1

    unite(a, b)



max_size = -min(root)

print(max_size)

N, M = list(map(int, input().split()))


class UnionFind:
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)
        if x == y:
            return
        if self.parents[x] > self.parents[y]:
            x, y = y, x
        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return len(self.roots())

    def all_group_members(self):
        return {r: self.members(r) for r in self.roots()}

    def __str__(self):
        return "\n".join("{}: {}".format(r, self.members(r)) for r in self.roots())


uf = UnionFind(N)
for _ in range(M):
    a, b = [int(x) - 1 for x in input().split()]
    uf.union(a, b)
ans = 0
for i in range(N):
    ans = max(ans, uf.size(i))
print(ans)

import sys

sys.setrecursionlimit(10**9)
N, M = list(map(int, input().split()))
root = [-1] * N


def r(x):
    if root[x] < 0:
        return x
    else:
        root[x] = r(root[x])
        return root[x]


def unite(x, y):
    x = r(x)
    y = r(y)
    if x == y:
        return
    root[x] += root[y]
    root[y] = x


def size(x):
    return -r(x)


for i in range(M):
    a, b = list(map(int, input().split()))
    a -= 1
    b -= 1
    unite(a, b)
max_size = -min(root)
print(max_size)

+import sys + +sys.setrecursionlimit(10**9) +root = [-1] * N -class UnionFind: -    def __init__(self, n): -        self.n = n -        self.parents = [-1] * n - -    def find(self, x): -        if self.parents[x] < 0: -            return x -        else: -            self.parents[x] = self.find(self.parents[x]) -            return self.parents[x] - -    def union(self, x, y): -        x = self.find(x) -        y = self.find(y) -        if x == y: -            return -        if self.parents[x] > self.parents[y]: -            x, y = y, x -        self.parents[x] += self.parents[y] -        self.parents[y] = x - -    def size(self, x): -        return -self.parents[self.find(x)] - -    def same(self, x, y): -        return self.find(x) == self.find(y) - -    def members(self, x): -        root = self.find(x) -        return [i for i in range(self.n) if self.find(i) == root] - -    def roots(self): -        return [i for i, x in enumerate(self.parents) if x < 0] - -    def group_count(self): -        return len(self.roots()) - -    def all_group_members(self): -        return {r: self.members(r) for r in self.roots()} - -    def __str__(self): -        return "\n".join("{}: {}".format(r, self.members(r)) for r in self.roots()) +def r(x): +    if root[x] < 0: +        return x +    else: +        root[x] = r(root[x]) +        return root[x] -uf = UnionFind(N) -for _ in range(M): -    a, b = [int(x) - 1 for x in input().split()] -    uf.union(a, b) -ans = 0 -for i in range(N): -    ans = max(ans, uf.size(i)) -print(ans) +def unite(x, y): +    x = r(x) +    y = r(y) +    if x == y: +        return +    root[x] += root[y] +    root[y] = x + + +def size(x): +    return -r(x) + + +for i in range(M): +    a, b = list(map(int, input().split())) +    a -= 1 +    b -= 1 +    unite(a, b) +max_size = -min(root) +print(max_size)