a) Canadian postal codes are of the form ' L1D1L2D2L3D3 ', where ' L ' is always a letter (A-Z) and ' D ' is always a digit (0-9). Suppose you have a company and you wish to keep track of customers who have similar postal codes, so the map might be (postal code, list of customers). Let the letters A-Z be coded with numbers 1 to 26 , for example code(B)=2, and let the digits be coded by their numerical values. i. For a hash function: hash(L1D1L2D2L3D3)=(i=13code(Li)+i=13code(Di))mod10 ii. Give an example of a postal code that begins with H3A and collides with H2B5X7. Give an example of a hash function that would never result in a collision. How large would the hash table need to be? b) Both hashing and binary search trees allow to efficiently store and access map entries. What are the advantages/disadvantages of each, which would make you choose one over another