排列组合算法之排列算法 字符串形势 C++ 小米nlp面试题

void swap(char& a, char& b){
    char temp = a;
    a = b;
    b = temp;
}


void pai(string& str, int start, int end, vector<string>& res){
    if(start == end){
        string st = str;
        res.emplace_back(st);
    }
    for(int i = start; i < end; i++){
        swap(str[start], str[i]);
        pai(str, start + 1, end, res);
        swap(str[i], str[start]);
    }
}

int test_perm(){
    string str = "abcde";
    vector<string> res;
    pai(str, 0, (int)str.size(), res);
    return 0;
}