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Nice set of questions you have there, will love to see you try out some of them before asking for help when stuck. Nice day & look forward to helping you.

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Nice one then, will check them out. Nice day

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Something that works:

Replace with )

'''
Created on Nov 7, 2013

@author: _where
'''
def ex4(x,y): 
    colWid = str(len(str(x ** y)))  # column width
    for i in range(x):
        for p in range (y):
            print('%s' % ('%' + colWid + 's') % (i+1)**(p+1), end=' ')
        print('\n')
        
def ex5(x):
    for k in [x for x in x.split(' ') if x != '']: print(k)

def ex6(x):
    a = [0,0,0,0,0] # store number of occurrence of each vowel
    b = ['a', 'e', 'i', 'o', 'u']
    for c in x:
        if (c == 'a' or c == 'A'):
            a[0] += 1
        elif (c == 'e' or c == 'E'):
            a[1] += 1
        elif (c == 'i' or c == 'I'):
            a[2] += 1
        elif (c == 'o' or c == 'O'):
            a[3] += 1
        elif (c == 'u' or c == 'U'):
            a[4] += 1
        else: pass
    if (max(a) == 0): print("No vowels in text"
    else:
        e = [d for d in range(5) if a[d] == max(a)]
        for f in e: print(b[f], '-->', a[f])
        
def ex7(x, key):
    z = ' '
    for a in x:
        if a == ' ':
            z += a
        else:
            z += chr(((ord(a) - 97 + key) % 26) +97)
    print("Encrypted/Decrypted value --> ", z) 

def ex8(x):
    lst = []
    
    # check if input is a valid expression for the reverse polish notation
    for a in x:
        if ((a.isdigit()) or (a == '+') or (a == '*') or (a == '-') or (a == ' ')): pass
        else: print("Invalid character in string --> ", a); return
	
    for a in x:
        if (a.isdigit()): lst.append(a)
        elif (a == '+' or a == '*' or a == '-'):
            if len(lst) >= 2:
                t = int(lst.pop())
                lst.append((eval('int(lst.pop()) %s t' % a)))
            else:
                print("Invalid input. Length of stack should be greater than or equal two"
                return
        else:
            print("Invalid character in string --> ", a)
    if len(lst) == 1: print(lst[0])
    else: print("Invalid input. Final length of stack should be one"

# Used to test the functions.
"""
if __name__ == '__main__':
    print ("Exercise Four: "
    x = (int)(input("How many rows do you want?")
    y = (int)(input("How many columns do you want?")
    ex4(x,y)
    
    print("\n\nExercise Five: "
    ex5(input("Enter line of text >>>    ")
    
    print("\n\nExercise Six: "
    ex6(input("Enter line of text >>>   ")
    
    print("\n\nExercise Seven: "
    x = input("Enter string to encrypt/decrypt >>>   "
    key = (int)(input("Enter Key >>  ")
    ex7(x,key)
    
    print("\n\nExercise Eight: "
    ex8(input("Enter string >>>  ")
"""

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boykelex: Thank you very much boss....can I have your facebook or twitter username Once again Big Thanks for the Help

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