資料結構複習之廣義表的建立和遍曆

標籤：

#include<iostream> #include<string>#include<cstring>#include<cstdlib>#include<list>#include<map>using namespace std;class GLNode{    public:        int tag;        string node;        class {            public:                GLNode *hp, *tp;            } ptr;};typedef GLNode *GList;class MyGList{    public:        static const int ERROR = -1;        static const int OK = 1;        static const int LIST = 2;        static const int NODE = 3;        list<string> sl;//廣義表的描述字串        map<string, string>mp;        GList L = NULL;        MyGList(list<string> sl){            this->sl = sl;             initMap();        }                void buildGList(){            string s = *sl.begin();            int pos = s.find_first_of("=");            if(pos!=s.npos)                createGList(L, s.substr(pos+1, s.length()));        }                void outGList(){            out(L);        }        private:        void server(string &s, string &hs){            int k = 0;//記錄尚未匹配的左括弧的個數            int i = 0;            for(i; i<s.length(); ++i) {                if(s[i]==‘(‘) ++k;                if(s[i]==‘)‘) --k;                if(k==0 && s[i]==‘,‘) break;            }            if(i < s.length()){                hs = s.substr(0, i);                s = s.substr(i+1, s.length()-(i+1));            } else {                hs = s;                s = "";            }        }                int initMap(){            for(list<string>::iterator i = sl.begin(); i!=sl.end(); ++i){                string s = *i, first, second;                   int pos = s.find_first_of("=");                   if(pos!=s.npos){                       first = s.substr(0, pos);                       second = s.substr(pos+1, s.length());                   } else {                       cout<<"廣義表的描述字串出錯!"<<endl;                       return ERROR;                   }                mp.insert(make_pair(first, second));            }        }                void out(GList Lx){            if(!Lx) return;            if(Lx->tag==NODE){                cout<<Lx->node<<endl;                return;            }            for(GList p=Lx; p; p=p->ptr.tp)                out(p->ptr.hp);        }                void createGList(GList &L, string s){            if(s=="()"){                //建立空表                L = NULL;             } else {                 L = new GLNode;//因為類中有string變數，不能用malloc, 否者賦值無效                 if(s.find(",")==s.npos && s.find("(")==s.npos && s.find(")")==s.npos){//原子結點                     if(mp.find(s) == mp.end()){                        L->tag = NODE;                        L->node = s;                    } else {//當s是只有一個大寫字母組成的時候，說明它是一個子表，繼續擴充                         createGList(L, mp[s]);//這塊出了開始bug， 調了好長時間                     }                } else {//非原子結點                     L->tag = LIST;                    GList p = L, q;                    s = s.substr(1, s.length()-2);                    do{                        string hs;                        server(s, hs);//分離表頭                         createGList(p->ptr.hp, hs);                        q = p;                        if(s!=""){//表尾不空                             p = new GLNode;                            p->tag = LIST;                            q->ptr.tp = p;                            }                    }while(s!="");                    q->ptr.tp = NULL;                }            }        }};int main(){    freopen("in.txt", "r", stdin);    list<string> sl;    string s;    while(cin>>s){        sl.push_back(s);    }    MyGList myGList(sl);    myGList.buildGList();    myGList.outGList();    return 0;}

測試資料：

D=(A,B,C)
A=()
B=(e)
C=(a,(b,c,d))

 

資料結構複習之廣義表的建立和遍曆