面试题 16.20. T9键盘
在老式手机上，用户通过数字键盘输入，手机将提供与这些数字相匹配的单词列表。每个数字映射到0至4个字母。给定一个数字序列，实现一个算法来返回匹配单词的列表。你会得到一张含有有效单词的列表。映射如下图所示：
示例 1:
输入: num = "8733", words = ["tree", "used"] 输出: ["tree", "used"]
示例 2:
输入: num = "2", words = ["a", "b", "c", "d"] 输出: ["a", "b", "c"]
提示：
num.length <= 1000words.length <= 500words[i].length == num.lengthnum中不会出现 0, 1 这两个数字原站题解
python3 解法, 执行用时: 40 ms, 内存消耗: 16.5 MB, 提交时间: 2022-11-17 22:43:53
string = ["abc", "def", "ghi", "jkl", "mno", "pqrs", "tuv", "wxyz"]
DICT = {}
for i in range(2, 10):
for w in string[i-2]:
DICT[w] = str(i)
class Solution:
def getValidT9Words(self, num: str, words: List[str]) -> List[str]:
def check(va):
for j, x in enumerate(num):
if DICT[va[j]] != x:
return False
return True
return [word for word in words if check(word)]
python3 解法, 执行用时: 48 ms, 内存消耗: 16.4 MB, 提交时间: 2022-11-17 22:38:59
class Solution:
def getValidT9Words(self, num: str, words: List[str]) -> List[str]:
dic = {'2': 'abc', '3': 'def', '4': 'ghi', '5': 'jkl', '6': 'mno', '7': 'pqrs', '8': 'tuv', '9': 'wxyz'}
return [word for word in words if all(char in dic[num[idx]] for idx, char in enumerate(word))]