n=int(input())
ls = [list(map(int,input().split())) for _ in range(n)]
cur =1
for i in range(n):
    for j in range(i+1,n):
        diff = [abs(ls[i][k]-ls[j][k]) for k in range(3)]
        diff_all = sum(diff)
        if all(di <= 5 for di in diff) and diff_all <= 10:
            cur +=1
print(cur)