freecodecamp--freecodecamp/curriculum/challenges/english/blocks/daily-coding-challenges-python/6a22d77ddf034bc4e35b1d57.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
6a22d77ddf034bc4e35b1d57	Challenge 350: Letter Distance	29	challenge-350

--description--

Given two strings of equal length, return the sum of the shortest distances between each pair of characters.

• The input will only contain lowercase letters
• The alphabet is treated as a circle, so the distance between a and z is 1.

--hints--

letter_distance("abc", "bcd") should return 3.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(letter_distance("abc", "bcd"), 3)`)
}})

letter_distance("abc", "xyz") should return 9.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(letter_distance("abc", "xyz"), 9)`)
}})

letter_distance("encrypt", "decrypt") should return 10.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(letter_distance("encrypt", "decrypt"), 10)`)
}})

letter_distance("algorithm", "codeblock") should return 43.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(letter_distance("algorithm", "codeblock"), 43)`)
}})

letter_distance("lobster", "penguin") should return 47.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(letter_distance("lobster", "penguin"), 47)`)
}})

letter_distance("alligator", "crocodile") should return 55.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(letter_distance("alligator", "crocodile"), 55)`)
}})

--seed--

--seed-contents--

def letter_distance(str1, str2):

    return str1

--solutions--

def letter_distance(str1, str2):
    total = 0
    for a, b in zip(str1, str2):
        diff = abs(ord(a) - ord(b))
        total += min(diff, 26 - diff)
    return total