The Romans have attacked again. This time they are much more than the Persians but Shapur is ready to defeat them. He says: 'A lion is never afraid of a hundred sheep'.
Nevertheless Shapur has to find weaknesses in the Roman army to defeat them. So he gives the army a weakness number.
In Shapur's opinion the weakness of an army is equal to the number of triplets i, j, k such that i < j < k and ai > aj > ak where ax is the power of man standing at position x. The Roman army has one special trait — powers of all the people in it are distinct.
Help Shapur find out how weak the Romans are.
The first line of input contains a single number n, the number of men in Roman army. Next line contains n different positive integers powers of men in the Roman army.
Input Size : N<=100000
Example:
INPUT
3
3 2 1
OUTPUT
1
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