题目链接：hdu 4964 Emmet

题目大意： 给定语句，按照语法翻译并输出。

解题思路：用递归模拟文法分析，主要注意几点：

1. 括号并且的情况：(fuck)(you)
2. 括号嵌套的情况：((fuck.you))
3. 优先输出id，然后是class（题目中有说）
4. 乘法的部分：fuck*2>you*3 （每次执行fuck时，you的地方同样被执行了3次）

   其他跑出样例基本没问题，具体看代码。

   #include 
        
          #include 
         
           #include 
          
            #include 
           
             #include 
            
              #include 
             
               using namespace std; typedef vector
              
                VS; const int manx = 1005; int mv, N; string str, word; bool isletter (char ch) { if (ch >= 'a' && ch <= 'z') return true; if (ch >= 'A' && ch <= 'Z') return true; if (ch >= '0' && ch <= '9') return true; if (ch == '_') return true; return false; } int changeTonumber () { int ret = 0; for (int i = 0; i < word.size(); i++) ret = ret * 10 + word[i] - '0'; return ret; } string getword () { string cur = ""; while (isletter(str[mv])) cur = cur + str[mv++]; mv--; return cur; } void gettoken () { if (mv == str.size()) { word = ""; return; } while (str[mv] == ' ') mv++; switch (str[mv]) { case '.': word = "."; break; case '#': word = "#"; break; case '>': word = ">"; break; case '(': word = "("; break; case ')': word = ")"; break; case '*': word = "*"; break; default: word = getword(); break; } mv++; } void putstring (string name, VS setid, VS setclass) { cout << "<" << name; if (setid.size() != 0) { cout << " id=\"" << setid[0]; for (int i = 1; i < setid.size(); i++) cout << " " << setid[i]; cout << "\""; } if (setclass.size() != 0) { cout << " class=\"" << setclass[0]; for (int i = 1; i < setclass.size(); i++) cout << " " << setclass[i]; cout << "\""; } cout << ">"; } void solve () { int ret = mv, x, y, ti = 1; string recstring = ""; gettoken(); while (word == "(") { solve(); // now word is ")"; gettoken(); // get a new token; } if (word == ">") { // after solve '()'; solve(); return; } if (word == "" || word == ")") return; string name; VS setclass, setid; while (true) { if (word == ".") { gettoken(); setclass.push_back(word); } else if (word == "#") { gettoken(); setid.push_back(word); } else if (word == ">") { putstring(name, setid, setclass); solve(); break; } else if (word == ")" || word == "") { putstring(name, setid, setclass); break; } else if (word == "*") { x = mv - 1; gettoken(); y = mv; ti = changeTonumber(); for (int i = x; i < y; i++) { recstring += str[i]; str[i] = ' '; } } else name = word; gettoken(); } cout << "
               "; for (int i = 1; i < ti; i++) { mv = ret; solve(); } for (int i = 0; i < recstring.size(); i++) str[i+x] = recstring[i]; } int main () { int cas; cin >> cas; while (cas--) { cin >> str; mv = 0; solve(); cout << endl; } return 0; }