{"id":19149,"date":"2021-11-29T03:04:32","date_gmt":"2021-11-29T03:04:32","guid":{"rendered":"https:\/\/assignmenttutors.net\/blog\/python-assign-code-h-w-computer-science-homework-help\/"},"modified":"2021-11-29T03:04:32","modified_gmt":"2021-11-29T03:04:32","slug":"python-assign-code-h-w-computer-science-homework-help","status":"publish","type":"post","link":"https:\/\/assignmenttutors.net\/blog\/python-assign-code-h-w-computer-science-homework-help\/","title":{"rendered":"Python assign code h\/w | Computer Science homework help"},"content":{"rendered":"
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\u00a0<\/p>\n

Start with the following Python code.\u00a0\u00a0<\/p>\n

alphabet = “abcdefghijklmnopqrstuvwxyz”\u00a0\u00a0\u00a0<\/p>\n

test_dups =\u00a0[“zzz”,”dog”,”bookkeeper”,”subdermatoglyphic”,”subdermatoglyphics”]\u00a0<\/p>\n

test_miss = [“zzz”,”subdermatoglyphic”,”the quick brown fox jumps over the lazy dog”]\u00a0<\/p>\n

# From Section 11.2 of:\u00a0<\/p>\n

# Downey, A. (2015). Think Python: How to think like a computer scientist. Needham, Massachusetts: Green Tree Press.\u00a0<\/p>\n

def histogram(s):
\u00a0 \u00a0 \u00a0d = dict()
\u00a0 \u00a0 \u00a0for c in s:
\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 if c not in d:
\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0d[c] = 1
\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 else:
\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0d[c] += 1
\u00a0 \u00a0 \u00a0return d\u00a0<\/p>\n

Copy the code above into your program but write all the other code for this assignment yourself. Do not copy any code from another source.\u00a0<\/strong><\/p>\n

Part 1\u00a0<\/strong><\/p>\n

Write a function called has_duplicates that takes a string parameter and returns True if the string has any repeated characters. Otherwise, it should return False.\u00a0\u00a0<\/p>\n

Implement has_duplicates by creating a histogram using the histogram function above. Do not use any of the implementations of has_duplicates that are given in your textbook. Instead, your implementation should use the counts in the histogram to decide if there are any duplicates.\u00a0<\/p>\n

Write a loop over the strings in the provided test_dups list. Print each string in the list and whether or not it has any duplicates based on the return value of has_duplicates for that string. For example, the output for “aaa” and “abc” would be the following.\u00a0<\/p>\n

aaa has duplicates
abc has no duplicates\u00a0<\/p>\n

Print a line like one of the above for each of the strings in test_dups.\u00a0<\/p>\n

Part 2\u00a0<\/strong><\/p>\n

Write a function called missing_letters that takes a string parameter and returns a new string with all the letters of the alphabet that are not<\/strong> in the argument string. The letters in the returned string should be in alphabetical order.\u00a0<\/p>\n

Your implementation should use a histogram from the histogram function. It should also use the global variable alphabet. It should use this global variable directly, not through an argument or a local copy. It should loop over the letters in alphabet to determine which are missing from the input parameter.\u00a0<\/p>\n

The function missing_letters should combine the list of missing letters into a string and return that string.\u00a0<\/p>\n

Write a loop over the strings in list test_miss and call missing_letters with each string. Print a line for each string listing the missing letters. For example, for the string “aaa”, the output should be the following.\u00a0<\/p>\n

aaa is missing letters bcdefghijklmnopqrstuvwxyz\u00a0<\/p>\n

If the string has all the letters in alphabet, the output should say it uses all the letters. For example, the output for the string alphabet itself would be the following.\u00a0<\/p>\n

abcdefghijklmnopqrstuvwxyz uses all the letters\u00a0<\/p>\n

Print a line like one of the above for each of the strings in test_miss.\u00a0<\/p>\n

Submit your Python program. It should include the following.\u00a0<\/p>\n