n=int(input())
ls = [list(map(int,input().split())) for _ in range(n)]
cur =0
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)
