"""
 array.py

 An Indexed Array "abstract data type"
 implemented as a python class

 Running it looks like this :

 $ python array.py
 A random IndexedArray of 10 numbers is  
  <IndexedArray size=10 values=[67, 95, 19, 65, 57, 77, 42, 63, 88, 17]>
 The values are  
  <IndexedArray size=10 values=[18, 2, 75, 77, 60, 57, 6, 82, 29, 79]>
 The smallest is  2


"""

from random import randint

class IndexedArray:
    """ An indexed array with a fixed size """

    def __init__(self, size):
        # special : invoked to initialize an array
        self.size = size          # the number of elements in this array
        self.values = [0]*size

    def get(self, i):
        """ return the i'th value in this array """
        return self.values[i]

    def put(self, i, value):
        """ assign the i'th entry in the array to this value """
        self.values[i] = value

    def __str__(self):
        # special : redefines str(array)
        return f"<IndexedArray size={self.size} values={self.values}>"
        
# ----------------------------------------------------------------------

def random_array(n):
    """ Return an IndexedArray of size n with random values from 1 to 10*n """
    result = IndexedArray(n)
    for i in range(n):
        result.put(i, randint(1, 10*n))
    return result

print("A random IndexedArray of 10 numbers is ", random_array(10))

# ------------------------------------------------------------------------

def smallest(array):
    """ Return the smallest value from an IndexedArray """
    # array.size       : number of elements
    # array.get(i)     : read value at i
    if array.size == 0:
        return None
    else:
        answer = array.get(0)
        for i in range(1, array.size):
            if array.get(i) < answer:
                answer = array.get(i)
        return answer

def main():
    values = random_array(10)
    print(" The values are ", values)
    small = smallest(values)
    print(" The smallest is ", small)

main()