Read a natural number `n` followed by `n` positive natural numbers. Print the greatest common divisor (GCD) of all `n` numbers, computed using **a recursive function** based on Euclid's algorithm. Define a recursive function `cmmdc(a, b)` with the relation: ``` cmmdc(a, 0) = a cmmdc(a, b) = cmmdc(b, a % b), for b > 0 ``` Then compute the GCD of all `n` numbers by successive reduction: start with the first number and combine it one by one with each of the remaining numbers using `cmmdc`.