Given an array of n integers (1<=n<=300000, 0<=arr[i]<=100000) and q queries (1<=q<=300000) where each query contains 2 integers l and r (1<=l<=r<=n), tell the gcd of all the elements in range l to r (both inclusive).

I am just not getting an idea on how to link query(l) and query(r) in fenwick tree(BIT)