Buggy python submission (verdict: Runtime Error):

N,M=map(int, input().split())
l=[[]for j in range(N)]
field=[True]*N
for i in range(M):
    a,b=map(int,input().split())
    l[a-1].append(b-1)
    l[b-1].append(a-1)
for i in range(N):
    l[i]=list(set(l[i]))

def dfs(x):
    conn=1
    field[x]=False
    for j in range(len(l[x])):
        if field[l[x][j]]:
            conn+=dfs(l[x][j])
    return conn

nax=0
for i in range(N):
    temp=dfs(i)
    nax=max(nax,temp)

print(nax)


Fixed submission:
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())

N,M=map(int,input().split())
uf=UnionFind(N)
for i in range(M):
    A,B=map(int,input().split())
    uf.union(A-1,B-1)
ans=0
for i in range(N):
    ans=max(ans,uf.size(i))

print(ans)

Buggy python submission (verdict: Runtime Error):

N,M=map(int, input().split())
l=[[]for j in range(N)]
field=[True]*N
for i in range(M):
    a,b=map(int,input().split())
    l[min(a,b)-1].append(max(a,b)-1)
for i in range(N):
    l[i]=list(set(l[i]))

def dfs(x):
    conn=1
    field[x]=False
    for j in range(len(l[x])):
        if field[l[x][j]]:
            conn+=dfs(l[x][j])
    return conn

nax=0
for i in range(N):
    temp=dfs(i)
    nax=max(nax,temp)

print(nax)


Fixed submission:
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())

N,M=map(int,input().split())
uf=UnionFind(N)
for i in range(M):
    A,B=map(int,input().split())
    uf.union(A-1,B-1)
ans=0
for i in range(N):
    ans=max(ans,uf.size(i))

print(ans)

Buggy python submission (verdict: Runtime Error):

N,M=map(int, input().split())
l=[[]for j in range(N)]
field=[True]*N
for i in range(M):
    a,b=map(int,input().split())
    l[min(a,b)-1].append(max(a,b)-1)

def dfs(x):
    conn=1
    field[x]=False
    for j in range(len(l[x])):
        if field[l[x][j]]:
            conn+=dfs(l[x][j])
    return conn

nax=0
for i in range(N):
    temp=dfs(i)
    nax=max(nax,temp)

print(nax)

Fixed submission:
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())

N,M=map(int,input().split())
uf=UnionFind(N)
for i in range(M):
    A,B=map(int,input().split())
    uf.union(A-1,B-1)
ans=0
for i in range(N):
    ans=max(ans,uf.size(i))

print(ans)

Buggy python submission (verdict: Runtime Error):

N,M=map(int, input().split())
l=[[]for j in range(N)]
field=[True]*N
for i in range(M):
    a,b=map(int,input().split())
    l[min(a,b)-1].append(max(a,b)-1)

def dfs(x):
    conn=1
    field[x]=False
    for j in range(len(l[x])):
        if field[l[x][j]]:
            conn+=dfs(l[x][j])
    return conn

nax=0
for i in range(N):
    temp=dfs(i)
    nax=max(nax,temp)

print(nax)

Fixed submission:
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())

N,M=map(int,input().split())
uf=UnionFind(N)
for i in range(M):
    A,B=map(int,input().split())
    uf.union(A-1,B-1)
ans=0
for i in range(N):
    ans=max(ans,uf.size(i))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import collections
import math

import numpy as np
from scipy.sparse.csgraph import connected_components
from scipy.sparse import csr_matrix

N,M=map(int, input().split())
l=[[0 for i in range(N)]for j in range(N)]
for i in range(M):
    a,b=map(int,input().split())
    l[a-1][b-1]=1


a = np.array(l)

n, labels = connected_components(a)

cc=collections.Counter(labels)
ans=max(cc.values())
print(ans)

Fixed submission:
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())

N,M=map(int,input().split())
uf=UnionFind(N)
for i in range(M):
    A,B=map(int,input().split())
    uf.union(A-1,B-1)
ans=0
for i in range(N):
    ans=max(ans,uf.size(i))

print(ans)

Buggy python submission (verdict: Runtime Error):
import collections
import math

import numpy as np
from scipy.sparse.csgraph import connected_components
from scipy.sparse import csr_matrix

N,M=map(int, input().split())
l=[[0 for i in range(N)]for j in range(N)]
for i in range(M):
    a,b=map(int,input().split())
    l[a-1][b-1]=1


a = np.array(l)
# print(type(a))
# # <class 'numpy.ndarray'>

n, labels = connected_components(a)

cc=collections.Counter(labels)
ans=max(cc.values())
print(ans)

Fixed submission:
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())

N,M=map(int,input().split())
uf=UnionFind(N)
for i in range(M):
    A,B=map(int,input().split())
    uf.union(A-1,B-1)
ans=0
for i in range(N):
    ans=max(ans,uf.size(i))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
N,M=map(int,input().split())
temp=[[0 for i in range(N)]for j in range(N)]

for i in range(M):
    a,b=map(int,input().split())
    temp[a-1][b-1]=1
    temp[b-1][a-1]=1
ans=0
for i in range(N):
    ans=max(ans,sum(temp[i]))

print(ans+1)

Fixed submission:
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())

N,M=map(int,input().split())
uf=UnionFind(N)
for i in range(M):
    A,B=map(int,input().split())
    uf.union(A-1,B-1)
ans=0
for i in range(N):
    ans=max(ans,uf.size(i))

print(ans)