# Hail, Ceasar!
# Lab 2
# Cody Mays
# October 6, 2009

import sys

valids = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']
theString = ''
newString = ''

def inlist(val, theList):
    overall = False

    # Make sure it's not 0 length
    if(len(val) == 0):
        return False
    
    for k in range(len(val)):
        specific = False
        
        for i in range(len(theList)):         
            if(val[k] == theList[i]):
                specific = True
                break;

            
        if(specific == False):
            overall = False
            break
        else:
            overall = True
        
    return overall


#Main...
if(len(sys.argv) > 1 and inlist(sys.argv[1], valids)):
    theString = raw_input("Please enter a string to encrypt>")

    for i in range(len(theString)):
        newChar = ''
        baseVal = ord(theString[i])
        
        if( (baseVal >= 65 and baseVal <= 90)): #capital
            if(baseVal + int(sys.argv[1]) > ord('Z') ):
                newChar = (((baseVal - ord('A')) + int(sys.argv[1]))%26) + 65
            else:
                newChar = baseVal + int(sys.argv[1])

            newString += chr( newChar )
             
        elif (baseVal >= 97 and baseVal <= 122): #lower
            if(baseVal + int(sys.argv[1]) > ord('z') ):
                newChar = (((baseVal - ord('a')) + int(sys.argv[1]))%26) + 97
            else:
                newChar = baseVal + int(sys.argv[1])

            newString += chr( newChar )
        else:                                   #everything else
            newString += theString[i]
    print newString
else:
    print 'invalid argument'