N = int(input())
I = [list(map(int, input().split())) for x in range(N)]
D = {}
S = 0
for n in range(N):
    for m in range(3):
        if I[n][m] not in D:
            D[I[n][m]] = 1
        elif D[I[n][m]] == 1:
            D[I[n][m]] = 0
            S += 1
        else:
            D[I[n][m]] = 1

for x in D.values():
    if x == 1:
        S += 1/4

print(int(S))