LeetCode #17: Letter Combinations of a Phone Number
β’ 60 words β’ 1 min β’ updated
LeetCode #17: Letter Combinations of a Phone Number:
python
class Solution:
def letterCombinations(self, digits: str) -> List[str]:
m = {
'2': 'abc',
'3': 'def',
'4': 'ghi',
'5': 'jkl',
'6': 'mno',
'7': 'pqrs',
'8': 'tuv',
'9': 'wxyz',
}
ans = []
def backtrack(candidate, digits):
if not digits:
ans.append(candidate)
return
for letter in m[digits[0]]:
backtrack(candidate + letter, digits[1:])
backtrack("", digits)
return ans