?LeetCode刷題實戰(zhàn)320：列舉單詞的全部縮寫

示例：
輸入: “word”
輸出:
[“word”, “1ord”, “w1rd”, “wo1d”, “wor1”, “2rd”, “w2d”, “wo2”, “1o1d”, “1or1”, “w1r1”, “1o2”, “2r1”, “3d”, “w3”, “4”]

class Solution {
public:
    vector<string> generateAbbreviations(string word) {
        int len=word.size();
        vector<string> res;
        res.push_back("");//初始結(jié)果
        for(int i=0;i<len;++i){
            string w=word.substr(i,1);//對每個字符位置進行處理
            int nums_s=res.size();
            //對之前出現(xiàn)過的每種結(jié)果進行更新
            for(int j=0;j<nums_s;++j){
                string tmp=res[j];
                res[j]+=w;//更新加上當前字符的方式
        
        //更新轉(zhuǎn)成當前數(shù)字的方式
                int k=tmp.size();
                //找出當前字符串的末尾的數(shù)字
                while(k>0&&isdigit(tmp[k-1])){
                    --k;
                }
                //根據(jù)當前字符串的末尾的字符是否是數(shù)字的情形，更新
                if(k==tmp.size()){
                    res.push_back(tmp+"1");
                }
                else{
                    res.push_back(tmp.substr(0,k)+to_string(1+stoi(tmp.substr(k,tmp.size()-k))));
                }
            }
        }
        return res;
    }
};