"""
[3088: 화분 부수기](https://www.acmicpc.net/problem/3088)
Tier: Bronze ??
Category: 구현
"""
D = [False] * 1100000
def solution():
l = [[*map(int, input().split())] for _ in range(int(input()))]
cnt = 1
for i in range(3):
D[l[0][i]] = True
for i in range(1, len(l)):
chk = False
for j in range(3):
if D[l[i][j]]:
chk = True
if not chk:
cnt += 1
for j in range(3):
D[l[i][j]] = True
return cnt
if __name__ == '__main__':
print(solution())