2026.9.10

17 电话号码的字母组合

MAPPING='','','abc','def','ghi','jkl','mno','pqrs','tuv','wxyz' class Solution: def letterCombinations(self, digits: str) -> List[str]: ans=[] n=len(digits) path=['']*n def dfs(i:int)->None: if i==n: ans.append(''.join(path)) return for a in MAPPING[int(digits[i])]: path[i]=a dfs(i+1) dfs(0) return ans

35 搜索插入位置

class Solution: def searchInsert(self, nums: List[int], target: int) -> int: left,right=-1,len(nums) while left+1