big integer in php

I want to take big integer input in PHP. I am using bcmath but i am not getting how to take such a big integer input.the input is of order 10^40…can someone plz tell how to do it?

The php-int size could be changed/configured using the constant PHP_INT_SIZE and also the maximum allowed size can be hanged/configured using the constant PHP_INT_MAX. But still the int-size platform dependent which is depend on the 32 bit or 64 bit Operating System. Go with 64 bit which might help you.

Or you can make use of BCMath

BCMath is used to give output or for calculation…it can give output upto order 10^40 or above…but what about taking input??can u explain with example??it will be really helpful

i was solving http://www.codechef.com/problems/AMIFIB/

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