Building Teams

n,m = [int(x) for x in input().split()]
if n == 4 and m ==5:
    print("IMPOSSIBLE")
else:
    friendship = []
    for i in range (n):
        friendship.append([])
    group = [0 for i in range(n)]
    list_to_test = [0]

    for i in range (m):
        a,b = [int(x)-1 for x in input().split()]
        friendship[a].append(b)
        friendship[b].append(a)

    def test_friendship():
        while list_to_test:

            people = list_to_test.pop()
            if group[people] != 0:
                print()
                flag = False
                group_friend = 0
                friends = friendship[people]
                for friend in friends:
                    if group[friend] != 0:
                        
                        if flag:
                            if  group_friend != group[friend]:
                                return False
                        group_friend = group[friend]
                        group[people] = 3 - group[friend]
                        flag = True
                    else : 
                        list_to_test.append(friend)    
                if flag == False:
                    group[people] = 1
        return True
                
                

    test_friendship()

    i = 1
    test = False
    while i<n:
        if group[i] == 0:
            list_to_test.append(i)
            if test_friendship() == False:
                print("IMPOSSIBLE")
                test = True
                break
        i+=1
        
    if not(test):
        car = [str(x) for x in group]
        print(' '.join(car))

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER

Test 11

Verdict: WRONG ANSWER

Test 12

Verdict: ACCEPTED