Cesar Cipher implemented in python

allalgorithms/string/cesarCipher.py

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+# String Algorithms
+# Contributed by: JordaoA
+#Cesar Cipher implemented in python
+
+class cipher():
+	#Constructor method
+	def __init__(self,posCipher,jump):
+		self.letters = ["A","B","C","D","E",
+			"F","G","H","I","J","K","L",
+			"M","N","O","P","Q","R","S",
+			"T","U","V","W","X","Y","Z"] #Alphabet in UPPERCASE
+		self.posCipher = posCipher #encrypted word
+		self.jump = jump #jump between the letters
+
+	#Method responsible for ignore the case of all letters of the word  
+	def ignoreCase(self):
+		newPosCipher = ""
+
+		for i in range(len(self.posCipher)):
+			newPosCipher += self.posCipher[i].upper()
+
+		self.posCipher = newPosCipher #transforming the old word 
+
+	#Method responsible for search index of each letter of the word in the alphabet
+	def returnIndex(self,element, listOfLetters):
+		index = 0 #letter index
+
+		for i in range(len(listOfLetters)):
+			if element == listOfLetters[i]:
+				index = i
+				break
+
+		return index
+
+	#Method responsible for deciphering the word given by the user according to the letter jump
+	def cipherC(self):
+
+		self.ignoreCase()
+		preCipher = "" #decipher word
+
+		for j in range(len(self.posCipher)):
+			index = self.returnIndex(self.posCipher[j], self.letters)
+
+			if (index - self.jump) > 25:
+				preCipher += self.letters[(index - self.jump) % 26]
+
+			else:
+				preCipher += self.letters[(index - self.jump)]
+
+		return preCipher