5道经典深度优先搜索与宽度优先搜索相关题目-词语阶梯

class Solution {
public:
    int ladderLength(string beginWord, string endWord, vector& wordList) {
        unordered_set dict(wordList.begin(), wordList.end());
        if(!dict.count(endWord)) return 0;
        int res=1,n=beginWord.size();
        unordered_set q1{{beginWord}}, q2{{endWord}};
        dict.erase(beginWord);
        while(!q1.empty() && !q2.empty()){
            ++res;
            unordered_set q;
            for(const string& w:q1){
                string cur = w;
                for(int i=0;i q2.size()){
                swap(q1, q2);
            }
        }
        return 0;
    }
};