n = int(input())
l = [input().split() for i in range(n)]

s = [[] for _ in range(20)]

for i in l:
    if i[0] == "0":
        s[int(i[1])-1] = i[2:]

    elif i[0] == "1":
        for j in range(20):
            if i[1] in s[j]:
                print(j+1)
                s[j].remove(i[1])
                break
        else:
            print(-1)

    else:
        s[int(i[1])-1] = []