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# 1

f = open('27-A(2) (1).txt')
n = int(f.readline())
# 1
c = []
for i in range(1,n+1):
    c.append(int(f.readline()))
s = 0
for i in range(n):
    for j in range(i+1, n):
        a = str(c[i]*c[j])
        if a[-6:] == '000000' and a[-7:] != '0000000':
            s+=1
print(s)

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