Like the title stated. I really need help with this problem. It's in my training camp for my country's national olympiad.

I'll simplify it for you guys.

Given three numbers X,Y,Z (X,Y,Z <= 9000),

Count all divisors of all number that is a product from three numbers a,b,c such that (a <= X,b <= Y, c <= Z) (a divisor and be counted again and again) modulo 2^30

To be more clear,a simple algorithm to solve it is:

res = 0

for i = 1...X

for j = 1...Y

for k = 1...Z

res = res + count_divisors(i*j*k)

count_divisors is a function that counts all positive divisors of an integer

It's obviously too slow

Find res modulo 2^30

Time limit is 2 seconds.

It's quite ridiculous guys. Thank you for any help!

Example : X = 2,Y = 2, Z = 2

the numbers are : 1 , 2 , 2 , 2 , 4 , 4 , 4 , 8

total divisors are 20.

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