diff --git a/algorithms/cryptography/columnar_transposition_cipher.py b/algorithms/cryptography/columnar_transposition_cipher.py
new file mode 100644
index 0000000..6f694e8
--- /dev/null
+++ b/algorithms/cryptography/columnar_transposition_cipher.py
@@ -0,0 +1,54 @@
+import math
+def encrypt(key, message):
+ ciphertext = []
+ for col in range(key):
+ position = col
+ while position < len(message):
+ ciphertext.append(message[position])
+ position += key
+ return ''.join(ciphertext)
+
+def decrypt(key, message):
+ numOfRows = math.ceil(len(message) / key)
+ plaintext = []
+ cipher = [*message]
+ remainder = len(message)%key
+ count=0
+ if(remainder != 0):
+ for i in range(0,len(message),numOfRows):
+ count += 1
+ if(count > remainder):
+ cipher.insert(i+numOfRows-1,'#')
+ cipher.append('#')
+ for row in range(numOfRows):
+ position = row
+ while(position < len(cipher)):
+ plaintext.append(cipher[position])
+ position += numOfRows
+ plaintext = [ele for ele in plaintext if ele != '#']
+ else:
+ for row in range(numOfRows):
+ position = row
+ while(position < len(message)):
+ plaintext.append(message[position])
+ position += numOfRows
+ return ''.join(plaintext)
+def main():
+ while(True):
+ print("1. Encrypt")
+ print("2. Decrypt")
+ print("3. Exit")
+ option = int(input("Enter the option: "))
+ if(option == 1):
+ text = input("Enter the plain text: ")
+ k = int(input("Enter the key: "))
+ cipher = encrypt(k,text)
+ print("Ciphertext: ", cipher)
+ if(option == 2):
+ text = input("Enter the ciphertext: ")
+ k = int(input("Enter the key: "))
+ plain = decrypt(k, text)
+ print("Plaintext: ", plain)
+ if(option == 3):
+ break
+main()
\ No newline at end of file
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