[LeetCode]Letter Combinations of a Phone Number

最新推荐文章于 2020-08-10 10:20:18 发布

原创最新推荐文章于 2020-08-10 10:20:18 发布 · 3k 阅读

0 ·

CC 4.0 BY-SA版权

LeetCode 专栏收录该内容

152 篇文章

订阅专栏

本文介绍了一个使用C++实现的电话号码对应的字母组合生成器。通过递归辅助函数完成从数字到预定义字母的映射，实现了所有可能的字符串组合。文章详细展示了如何根据输入的数字序列生成所有可能的字母组合。

class Solution {
//static declare and definition with local scope
public:
	void letterCombinations_aux(int step, string& path, vector<string>& ans, const string& digits)
	{
		//pay attention to this kind of statement
		const static string strT[10] = {"","","abc","def","ghi","jkl","mno","qprs","tuv","wxyz"};
		if(step == digits.size())
		{
			ans.push_back(path);
			return;
		}
		for(int i = 0; i < strT[digits[step]-'0'].size(); ++i)
		{
			path.push_back(strT[digits[step]-'0'][i]);
			letterCombinations_aux(step+1, path, ans, digits);
			path.pop_back();
		}
	}
    vector<string> letterCombinations(string digits) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        string path;
		vector<string> ans;
		int step = 0;
		letterCombinations_aux(step, path, ans, digits);
		return ans;
    }
};