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 <= 1000 words.length <= 500 words[i].length == num.length num中不会出现 0, 1 这两个数字
将26个字母按顺序将对应的数字存入数组,再比对输入的数字是否符合
class Solution { public List<String> getValidT9Words(String num, String[] words) { List<String> res = new ArrayList<>(); char[] map = {'2','2','2','3','3','3','4','4','4','5','5','5','6','6','6','7','7','7','7','8','8','8','9','9','9','9'}; for(String word : words){ int index = 0; boolean flag = true; for(char c : word.toCharArray()){ char n = map[c-'a']; if(n != num.charAt(index++)){ flag = false; break; } } if(flag){ res.add(word); } } return res; } }
原文链接:https://www.cnblogs.com/guizimo/p/13456463.html