1 import numpy 2 key_word = str.upper(input('请输入秘钥：')) 3 key_set = set() 4 for i in key_word: 5 if i.isalpha(): 6 key_set.add(i) 7 key_set = list(key_set) 8 key_set.sort(key=key_word.index) 9 for i in range(26): 10 ch = chr(i+0x41) 11 if ch not in key_set: 12 key_set.append(ch) 13 key_set.remove('J') 14 15 table = numpy.array(key_set) 16 table = numpy.reshape(table,(5,5)) 17 model = int(eval(input('请输入填充模式（0：按列，1：按行）：'))) 18 if model == 0: 19 table = table.T#by column 20 else: 21 pass 22 print(r'''密钥矩阵（i/j同位）： 23 {}'''.format(table)) 24 25 mes = str.upper(input('请输入明文：')) 26 M = [] 27 for i in mes: 28 if i.isalpha(): 29 M.append(i) 30 try: 31 M[M.index('J')] = 'I' 32 except: 33 pass 34 35 def yjudge(table,ra,ca,rb,cb): 36 if ra == rb: 37 return 1 38 elif ca == cb: 39 return 2 40 else: 41 return 3 42 43 44 i = 0 45 C = '' 46 while True: 47 len_m = len(M) 48 left = len_m - i 49 if left == 0: 50 break 51 elif left == 1: 52 M.append('X') 53 elif M[i] == M[i+1]: 54 M.insert(i+1,'X') 55 else: 56 pass 57 ra,ca = numpy.where(table == M[i]) 58 ra = ra[0] 59 ca = ca[0] 60 rb,cb = numpy.where(table == M[i+1]) 61 rb = rb[0] 62 cb = cb[0] 63 #print(table[ra,ca],table[rb,cb]) 64 ytype = yjudge(table,ra,ca,rb,cb) 65 #print(ytype) 66 if ytype == 1:#同行在右侧 67 C = C+table[ra,(ca+1)%5] 68 C = C+table[rb,(cb+1)%5] 69 elif ytype == 2:#同列在下侧 70 C = C+table[(ra+1)%5,ca] 71 C = C+table[(rb+1)%5,cb] 72 else:#不同行不同列，取同行的那个角 73 C = C+table[ra,cb] 74 C = C+table[rb,ca] 75 i += 2 76 print(r'''密文：{}'''.format(C))
测试样例（同wikipedia）：
请输入秘钥：playfair example 请输入填充模式（0：按列，1：按行）：1 密钥矩阵（i/j同位）： [['P' 'L' 'A' 'Y' 'F'] ['I' 'R' 'E' 'X' 'M'] ['B' 'C' 'D' 'G' 'H'] ['K' 'N' 'O' 'Q' 'S'] ['T' 'U' 'V' 'W' 'Z']] 请输入明文：Hide the gold in the tree stump 密文：BMODZBXDNABEKUDMUIXMMOUVIF