Algorithms #2 (Extreme pain)

import random
import string
from math import comb, log
from timeit import default_timer as timer

TEST = False

def main():
    for case in range(1,6):
        run(10**case)

def run(cases):
    coupons = CouponGenerator(cases)
    coupons.generate()
    coupons.array.sort()

    start = timer()
    codes = coupons.array
    tablesize = round(10**5+7)

    variants = tableVariants(codes)
    #printTable(variants)

    hashesTable = hashes(variants, tablesize)
    #printTable(hashesTable)

    hashTAble = hashTable(hashesTable, codes, tablesize)
    #printTable(hashTAble)

    searchForPairs(hashTAble, tablesize)
    end = timer()
    print("Took {} seconds for the {} cases.".format(end-start, cases))

def searchForPairs(table, tablesize):
    checkedHashes = []
    hammingPairs = 0
    for i in range(len(table)):
        for j in range(len(table[0])):
            if len(table[i][j]) > 1:
                tempRefHash = [calcHash(code, tablesize) for code in table[i][j]]
                if all(item in checkedHashes for item in tempRefHash) == False:
                    hammingPairs += comb(len(table[i][j]), 2)
                    checkedHashes.append(tempRefHash)
    print("There are {} hamming pairs.".format(hammingPairs))

def hashTable(hashes, codes, tablesize):
    table = [[[] for _ in range(len(codes[0]))] for _ in range(tablesize)]
    for i in range(len(codes)):
        for j in range(len(codes[0])):
            if codes[i] in table[hashes[i][j]][j]:
                continue
            table[hashes[i][j]][j].append(codes[i])
    return table

def calcHash(code, tablesize):
    constant = 137
    codeNum = str2char(code)
    lastHashValue = 0

    for character in codeNum:
        if character == "*":
            continue
        lastHashValue = (ord(character) + constant * lastHashValue) % tablesize
    return lastHashValue

def hashes(variants, tablesize):
    table = [[[] for _ in range(len(variants[0]))] for _ in range(len(variants))]
    for i in range(len(variants)):
        for j in range(len(variants[0])):
            table[i][j] = calcHash(variants[i][j], tablesize)
    return table

def tableVariants(codes):
    table = [[[] for _ in range(len(codes[0]))] for _ in range(len(codes))]
    for h in range(len(codes)):
        string = codes[h]
        for i in range(0, len(string)):
            table[h][i] = string[0:i] + "*" + string[i+1:len(string)]
    return table

def printTable(table):
    for row in table:
        for col in row:
            print(col, end="\t")
        print("\n")

class CouponGenerator:
    def __init__(self, n):
        self.array = []
        self.n = n
    def printArray(self):
        for i in self.array:
            print(i)
    def generate(self):
        if TEST:
            self.array = ['WELC1234OTHE', 'IEEE1234MEXZ', 'AAAA0000ACAD', 'AAAA0000ACAF', 'AAAA0000ACAB', 'AAAA0000ABAB']
        else:
            for _ in range(self.n):
                self.array.append(''.join((''.join(random.SystemRandom().choice(string.ascii_uppercase) for _ in range(4)),''.join(random.SystemRandom().choice(string.digits) for _ in range(4)),''.join(random.SystemRandom().choice(string.ascii_uppercase) for _ in range(4)))))
        print(self.n, "coupons generated.")

def str2num(code):
    '''Δέχεται ως όρισμα μία ακολουθία δεδομένων και την μετατρέπει
    σε λίστα τύπου ακέραιου'''
    numCode = []
    for character in code:
        if ord(character) >=65 and ord(character) <= 90:
            numCode.append(ord(character)-54)
        else:
            if character == "*":
                continue
            numCode.append(int(character))
    return numCode

def str2char(code):
    '''Δέχεται ως όρισμα μία ακολουθία δεδομένων και την μετατρέπει
    σε λίστα τύπου χαρακτήρα'''
    numCode = []
    for character in code:
        numCode.append(character)
    return numCode

def nextPrime(n):
    notPrime = []
    isPrime = []
    for i in range (n+1, n+200):
        notPrime.append(i)
    for j in notPrime:
        prime = True
        for x in range(2, j-1):
            if j % x == 0:
                prime = False
                break
        if prime:
            isPrime.append(j)
    return min(isPrime)

if __name__ == "__main__":
    main()