int input sch k40 40 k4030 40 for in range int input 40 b1 40 40 40 if

n = int(input())
sch = 0
k40 = [0]*40
k4030 = [0]*40
q = 0
for i in range(n):
    a = int(input())
    b = a%40; b1 = (40 - b%40)%40
    if a >= 30:
        sch += k40[b1] + k4030[b1]
        k4030[b] += 1
    else:
        sch += k4030[b1]
        k40[b] += 1
print(sch)