Python: Get all possible two digit letter combinations from a digit string

Python Basic - 1: Exercise-13 with Solution

Write a Python program to get all possible two-digit letter combinations from a 1-9 digit string.

string_maps = {
"1": "abc",
"2": "def",
"3": "ghi",
"4": "jkl",
"5": "mno",
"6": "pqrs",
"7": "tuv",
"8": "wxy",
"9": "z"
}

Pictorial Presentation:

Sample Solution:

Python Code:

def letter_combinations(digits):
    if digits == "":
        return []
    string_maps = {
        "1": "abc",
        "2": "def",
        "3": "ghi",
        "4": "jkl",
        "5": "mno",
        "6": "pqrs",
        "7": "tuv",
        "8": "wxy",
        "9": "z"
    }
    result = [""]
    for num in digits:
        temp = []
        for an in result:
            for char in string_maps[num]:
                temp.append(an + char)
        result = temp
    return result

digit_string = "47"
print(letter_combinations(digit_string))
digit_string = "29"
print(letter_combinations(digit_string))

Sample Output:

['jt', 'ju', 'jv', 'kt', 'ku', 'kv', 'lt', 'lu', 'lv']
['dz', 'ez', 'fz']

Flowchart:

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Python Code Editor :

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