Given space$-$separated positive numbers. Write a program to find

the first index in the given numbers such that the product of all the

numbers before the index is equal to the product of all the numbers

after the index.

Note

The input will always contain atleast an index such

that the product of all the numbers before the

index is equal to the product of all the numbers

after the index.

Input

The input will be a single line containing space$-$separated positive

numbers.