#!/usr/bin/env python
# coding: utf-8

# # Strings
# - string is a compound data type; sequence of characters
# - can work with string as a single thing
# - string variables are objects with their own attributes and methods
# - help(str) to see all the methods
# - commonly used methods: upper(), lower(), swapcase(), capitalize(), endswith(), isdigit(), find(), center(), count(), split(), etc.

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help(str)


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ss = "Hello there beautiful World!"
tt = ss.upper()
print(tt)
print(tt.capitalize())
alist = tt.split()
print(alist)


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# examples of some methods
ss.count('o')
ss[0] = 'h'


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# write a program to evaluate math operations
# 2+2
# 3*3
eval('2+2')
eval('print ("hello")')


# ## working with the parts of a string
# - string can be sliced using [index] or [inclStartIndex:ExclEndIndex:step] bracket operator
# - negative indices are allowed - quick palindrome example
# - string is immutable
# - len() built-in function returns the length of a string

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# examples
s = "Pirates of the Caribbean"
# print just the pirates 
#print(len(s[0:7]))
# print the
#print(s[-1:])
theIndex = s.find("the")
print(theIndex)
print(s[theIndex:theIndex+4])
# print Caribbean - hint use find function
print(s[:])
print(s[1:])
print(s[-1::-2])


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lastSpace = s.rfind(' ')
print(lastSpace)


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a= "rarj"
print ('palindrome') if a==a[::-1] else print('not palindrome')


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s = "Pirates of the Caribbean."
print(s[len(s)-1])


# ## string traversal using for and while loop

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# example for loop
for i in range(len(s)):
    print(s[i], end=' ')


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for c in s:
    print(c, end=' ')


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someStr = """afAdf@#456'""""


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# example while loop


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i = 0
while i < len(s):
    print(s[i], end= ' ')
    i += 1


# ## string comparison
# - strings can be compared
# - compares lexicographically (ascii values)
# 

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print(ord('a'))
print(ord('A'))


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# e.g.
print("apple" == "Apple")# false
print("apple" >= "ball") # false
print("apple" >= "Apple") # true


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print("apple" == "Apple") # false


# ## in and not in operators
# - help quickly test for membership

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print("p" in "apple")
print("pe" in "apple")
print("aple" not in "apple")


# ## cleaning up strings
# - remove punctuations

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# create a new string removing punctuations from the following string
# string module
ss = '"Well, I never did!", said Alice.'
print(ss)


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print(ord('a'))


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newStr = ''
for c in ss:
    if ord(c) == ord(' '):
        newStr += c
    elif ord(c) >= ord('A') and ord(c) <= ord('Z'):
        newStr += c
    elif ord(c) >= ord('a') and ord(c) <= ord('z'):
        newStr += c
print(newStr)


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newStr1 = newStr.lower()
print(newStr1)


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words = newStr1.split()
print(words)


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for w in words:
    print(w)


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import string
help(string)


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print(string.punctuation)


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ss


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newStr = ''
for c in ss:
    if c in string.ascii_lowercase:
        newStr += c
    elif c in string.ascii_uppercase:
        newStr += c
    elif c == ' ':
        newStr += ' '
        
print(newStr)
print(newStr.lower())


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def cleanup(someStr):
    newStr = ''
    for c in someStr:
        if c.islower():
            newStr += c
        elif c.isupper():
            newStr += c
        elif c.isspace():
            newStr += c
    return newStr


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s = cleanup(ss)
print(s)


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help(str)


# ## string formatting
# - format method
# - use {} as replacement field
# - numbers in curly braces are optional; determine which argument gets substituted
# - each of the replace fields can also contain a format specification
#     - < left alignment, > right, and ^ center, e.g. {1:<10}
#     - 10 is width
#     - type conversion such as f for float (.2f two decimal places), x for hex, etc.

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name = "Arthur"
age = 25
s1 = "His name is {}!".format(name)
print(s1)


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# note age and name are provided in reverse order
print("His name is {1} and {1} is {0} years old.".format(age, name))


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n1 = 4
n2 = 5
s3 = "2**10 = {0} and {1} * {2} = {3:.2f}".format(2**10, n1, n2, n1 * n2)
print(s3)


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n1 = "Paris"
n2 = "Whitney"
n3 = "Hilton"

print("Pi to three decimal places is {0:.3f}".format(3.1415926))
print("123456789 123456789 123456789 123456789 123456789 123456789")
print("|||{0:<15}|||{1:^15}|||{2:>15}|||Born in {3}|||"
        .format(n1,n2,n3,1981))
print("The decimal value {0} converts to hex value {0:x}"
        .format(123456))


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letter = """
Dear {0} {2}.
 {0}, I have an interesting money-making proposition for you!
 If you deposit $10 million into my bank account, I can
 double your money ...
"""

print(letter.format("Paris", "Whitney", "Hilton"))
print(letter.format("Bill", "Warren", "Jeff"))


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layout = "{0:>4}{1:>6}{2:>6}{3:>8}{4:>13}{5:>24}"

print(layout.format("i", "i**2", "i**3", "i**5", "i**10", "i**20"))
for i in range(1, 11):
    print(layout.format(i, i**2, i**3, i**5, i**10, i**20))


# ## exercises
# 
# 1 print a neat looking multiplication table like this:
# <pre>
#         1   2   3   4   5   6   7   8   9  10  11  12
#   :--------------------------------------------------
#  1:     1   2   3   4   5   6   7   8   9  10  11  12
#  2:     2   4   6   8  10  12  14  16  18  20  22  24
#  3:     3   6   9  12  15  18  21  24  27  30  33  36
#  4:     4   8  12  16  20  24  28  32  36  40  44  48
#  5:     5  10  15  20  25  30  35  40  45  50  55  60
#  6:     6  12  18  24  30  36  42  48  54  60  66  72
#  7:     7  14  21  28  35  42  49  56  63  70  77  84
#  8:     8  16  24  32  40  48  56  64  72  80  88  96
#  9:     9  18  27  36  45  54  63  72  81  90  99 108
# 10:    10  20  30  40  50  60  70  80  90 100 110 120
# 11:    11  22  33  44  55  66  77  88  99 110 121 132
# 12:    12  24  36  48  60  72  84  96 108 120 132 144
# </pre>

# 2 write a program that calculates number of tirals required to guess a 3 digit passcode 777 (starting from 000, 001, 002, 003, 004, 005..., 010, etc.) using some brute force technique.