Lab 3?–?CPS?106

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This lab helps you practice string manipulation and recursive implementation.

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1. ??You have written an essay that should?be?at?least?five pages?long,?but?it?is?only?4.5?pages.?You ??decide?to?use?your?new?python?skills?to?stretch?it?out?by?putting?spaces?between?each?letter?and the next. Write a function that takes?a?string?and?a?number?and prints?out?the?string?with?number of spaces between each pair of?letters.

def spacedout(str,?numSpaces)

For example spacedout(“It was a dark and stormy night”,?1)?returns

“I t??w a s ??a ??d a?r?k ??a?n?d??s?t?o?r?m y ??n i?g h?t”

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2. ??Write a python program that returns the reverse of?a given string.

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def?reverse(str1)

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For?example reverse(“I am here”) returns?“ereh ma?I”. Using?this,?write?a?function?that?checks?if?a given string is a palindrome.

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def isPalindrome(str1)

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3. ??Write?a recursive function that?prints?all?the permutations?of a?given?string.?For?example,?for?the input “abcd” the?function should print:

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abcd,?abdc,?acbd,?acdb,?adbc,?adcb,?bacd,?badc,?bcad,?bcda,?bdac,?bdca,?cabd,?cadb,?cbad,?cbda,?cdab, cdba, dabc, dacb,?dbac,?dbca,?dcab,?dcb

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4. ??Given?an?integer?n,?write?a?python?program?that?finds?the?digit?with?the?highest?number?of

occurrences in n. For example, for n =?823778823478234768238?the program?should?return?8.

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def findHighestOccur(n)

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Test your program on the following inputs:

n?=?983254682376587235235

n?=?767347657623764765766665

n?=?923740923466234678666872628347666

代碼：

#3-1

# -*- coding: utf-8 -*-

"""

Created on Sun Jan? 8 10:17:36 2023

@author: pc

"""

str1 ='It was a dark and stormy night'

space2 = ' '

def spacedout(str, space):

? ? strResult = ''

? ? for a in str:

? ? ? ? a = a + space

? ? ? ? strResult = strResult + a

? ? ? ??

? ? print(strResult)

print(str1)

spacedout(str1, space2)

#3-1-2

# -*- coding: utf-8 -*-

"""

Created on Sun Jan? 8 10:29:47 2023

@author: pc

"""

s = 'It was a dark and stormy night'

? ??

def spacedout(str):

? ? addspace = ' '

? ? return addspace.join('It was a dark and stormy night')

print(spacedout(s))

# -*- coding: utf-8 -*-

"""

Created on Sun Jan? 8 10:49:56 2023

@author: pc

"""

# 3-2

# -*- coding: utf-8 -*-

"""

Created on Sun Jan? 8 10:17:36 2023

@author: pc

"""

str1 ='It was a dark and stormy night'

space2 = ' '

def spacedout(str, space):

? ? strResult = ''

? ? i? = 0

? ? for i in range(len(str)):

? ? ? ? a = str[len(str) - i - 1]

? ? ? ? strResult = strResult + a

? ? ? ??

? ? print(strResult)

print(str1)

spacedout(str1, space2)

#3-2?reverse

# -*- coding: utf-8 -*-

"""

Created on Sun Jan? 8 10:54:17 2023

@author: pc

"""

s = "I am here"

def reverse(str):

? ? n = len(str)

? ? l = ' '

? ? for i in range(n):

? ? ? ? l = l + str[n-i-1]

? ??

? ? return l

print(reverse(s))