From 7d554d38c4f757f6beb7f91c617e1231fadefc2f Mon Sep 17 00:00:00 2001
From: Saturneric <eric.bktu@gmail.com>
Date: Sat, 24 Apr 2021 19:53:36 +0800
Subject: [PATCH] Initial Commit.

---
 CMakeLists.txt                    |   8 +
 cmake-build-debug/syntaxInput.txt |   1 +
 main.cpp                          | 444 ++++++++++++++++++++++++++++++
 3 files changed, 453 insertions(+)
 create mode 100644 CMakeLists.txt
 create mode 100644 cmake-build-debug/syntaxInput.txt
 create mode 100644 main.cpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..79ad47e
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.17)
+project(syntaxParser)
+
+find_package(Boost REQUIRED)
+
+set(CMAKE_CXX_STANDARD 14)
+
+add_executable(syntaxParser main.cpp)
\ No newline at end of file
diff --git a/cmake-build-debug/syntaxInput.txt b/cmake-build-debug/syntaxInput.txt
new file mode 100644
index 0000000..8f05177
--- /dev/null
+++ b/cmake-build-debug/syntaxInput.txt
@@ -0,0 +1 @@
+struct_type->"struct" ID "{" member_list "}" EOF
diff --git a/main.cpp b/main.cpp
new file mode 100644
index 0000000..cdef265
--- /dev/null
+++ b/main.cpp
@@ -0,0 +1,444 @@
+#include <iostream>
+#include <ctime>
+#include <fstream>
+#include <vector>
+#include <string>
+#include <sstream>
+#include <set>
+#include <map>
+
+using namespace std;
+
+using std::vector;
+using std::string;
+using std::stringstream;
+using std::pair;
+
+struct Symbol {
+
+    const int index;
+    const string name;
+    const bool terminator;
+
+    Symbol(int index, const string & name, bool terminator):
+    index(index),
+    name(name),
+    terminator(terminator)
+    {}
+
+};
+
+class SymbolTable {
+    int index = 0;
+    map<string, Symbol> table;
+
+public:
+
+    int addSymbol(const string& name, bool terminator) {
+        const auto &it = table.find(name);
+        if ((it) != table.end()) {
+            return it->second.index;
+        }
+        Symbol symbol = Symbol(index++, name, terminator);
+        table.insert(pair<string, Symbol>(symbol.name, symbol));
+        return symbol.index;
+    }
+};
+
+ifstream input("syntaxInput.txt");
+
+
+map<string, set<string>> productions;//读入文件后，存放产生式
+map<string, set<string>> project;//在每个产生式右部前面加上点，得到初始项目集
+map<int, set<string>> StateSet;//状态
+map<int, set<string>> StateSetTemp;
+string css_by_order[20];
+string link[12][12];//存放各个状态之间的关系
+
+SymbolTable symbolTable;
+
+vector<vector<string>> ActionTable;
+
+vector<vector<int>> GoToTable;
+
+set<string> Vn;
+set<string> Vt;
+
+vector<string> vn_index;
+vector<string> vt_index;
+
+bool isVn(char ch) {
+    if (ch >= 'A' && ch <= 'Z') {
+        return true;
+    } else{
+        return false;
+    }
+}
+
+
+// 去掉首尾空格
+string& trim(string &&str) {
+    if (str.empty()) {
+        return str;
+    }
+
+    str.erase(0,str.find_first_not_of(' '));
+    str.erase(str.find_last_not_of(' ') + 1);
+    return str;
+}
+
+//得到最初项目集
+void getProject() {
+    productions["S\'"].insert("S");
+    //读入文法文件
+    int k = 1;
+    string temp_line;
+    while (getline(input, temp_line)) {
+        auto middle_index = temp_line.find("->", 0);
+
+
+        if(middle_index == string::npos) {
+            throw runtime_error("-> NOT FOUND");
+        }
+
+        string front = trim(temp_line.substr(0, middle_index));
+
+        string back = trim(temp_line.substr(middle_index + 2, temp_line.size() - middle_index - 2));
+
+        stringstream terminator, non_terminator;
+        bool is_terminator = false;
+        for(const auto &c : back) {
+            if (c == '\"') {
+                if(is_terminator) {
+                    symbolTable.addSymbol(trim(terminator.str()), true);
+                    terminator.str("");
+                    terminator.clear();
+                }
+                is_terminator = !is_terminator;
+                continue;
+            }
+            if(c == ' ') {
+                string temp_symbol = trim(non_terminator.str());
+                if(!temp_symbol.empty()) {
+                    symbolTable.addSymbol(trim(non_terminator.str()), false);
+                    non_terminator.str("");
+                    non_terminator.clear();
+                }
+                continue;
+            }
+            if(is_terminator) {
+                terminator << c;
+            } else {
+                non_terminator << c;
+            }
+        }
+
+        productions[temp_line.substr(0, 1)].insert(temp_line.substr(3, temp_line.length() - 3 + 1));
+        css_by_order[k++] = temp_line;
+    }
+    //构造基本项目集，即圆点位于右部开头的位置
+    string dot = "*";
+    for(map<string, set<string>>::iterator it = productions.begin(); it != productions.end(); it++) {
+        for(set<string>::iterator ij =it->second.begin(); ij != it->second.end(); ij++) {
+            string startStr = *ij;
+            startStr.insert(0, dot, 0, 1);
+            project[it->first].insert(startStr);
+        }
+    }
+}
+
+void Init_I0() {
+    StateSet[0].insert("S'->*S");
+    //先将所有的左部为S的产生式加入0号状态中
+    for(map<string, set<string> >::iterator it = project.begin(); it != project.end(); it++) {
+        if ((it->first) == "S") {
+            for(set<string>::iterator ij = it->second.begin(); ij != it->second.end(); ij++) {
+                StateSetTemp[0].insert(it->first + "->" + *ij);
+            }
+        }
+    }
+    //根据I0状态中已知内容，添加后续
+    while (! StateSetTemp[0].empty()){
+        set<string>::iterator it = StateSetTemp[0].begin();
+        string it_str = *it;//暂时集合中的每一条产生式
+        //如果点后面是非终结符，在project例找到它能推出来的产生式，加入temp,
+        if (isVn(it_str[4])) {
+            string after_dot_ch = it_str.substr(4,1);
+            for(set<string>::iterator css = project[after_dot_ch].begin(); css != project[after_dot_ch].end(); css++) {
+                StateSetTemp[0].insert(after_dot_ch + "->" + *css);
+            }
+            StateSetTemp[0].erase(it_str);
+            StateSet[0].insert(it_str);
+        }else if(! isVn(it_str[4])) {
+            StateSetTemp[0].erase(it_str);
+            StateSet[0].insert(it_str);
+        }
+    }
+}
+
+string MoveDot(string s, int pos) {
+    s.erase(pos,1);
+    s = s.substr(0, pos+1) + "*" + s.substr(pos+1, s.length()-pos);
+    return s;
+}
+
+void GenerateState() {
+    Init_I0();
+    int i = 0;
+    int state_num = 0;
+    string enter;
+    //对于每一个状态
+    while (i < StateSet.size()) {
+        map<string, set<string>> after_dot_ch;
+        //构造该状态中的after_dot_ch的map，first为点后面的字母，即输入字母，second为输入字母为first时的项目
+        for (set<string>::iterator it = StateSet[i].begin(); it != StateSet[i].end(); it++) {//对于此状态的每一个项目
+            int dot_pos = (*it).find("*");
+            if (dot_pos + 1 != (*it).length()) {
+                string s = (*it).substr(dot_pos + 1, 1);//点后面的字母
+                after_dot_ch[s].insert(*it);
+            }
+        }
+        if (after_dot_ch.size() == 0) {
+            i++;
+            continue;
+        }
+        for (map<string, set<string>>::iterator adc = after_dot_ch.begin(); adc != after_dot_ch.end(); adc++) {
+            enter = adc->first;
+            state_num++;
+            for (set<string>::iterator p = adc->second.begin(); p != adc->second.end(); p++) {
+                int dot_pos = (*p).find("*");
+                string moved_proj = MoveDot(*p, dot_pos);
+                int moved_dot_pos = (moved_proj).find("*");
+                StateSet[state_num].insert(moved_proj);
+
+                string moved_adc = moved_proj.substr(moved_dot_pos + 1, 1);
+                if (isVn(moved_adc[0])) {
+                    //如果点移动后的字符串中，点后字母是非终结符，则将以该非终结符开头的project加入该状态
+                    for (set<string>::iterator proj_css = project[moved_adc].begin();
+                         proj_css != project[moved_adc].end(); proj_css++) {
+                        StateSet[state_num].insert(moved_adc + "->" + (*proj_css));
+                    }
+                }
+            }
+            //--------判断之前是否有与新产生的状态相等的--------
+            bool is_equal = false;
+            for (int j = 0; j < state_num; ++j) {
+                if (StateSet[state_num].size() == StateSet[j].size()) {
+                    for (set<string>::iterator str = StateSet[j].begin(); str != StateSet[j].end(); str++) {
+                        if (StateSet[state_num].count(*str) == 0){
+                            break;
+                        } else{
+                            link[i][j] = enter;
+                            is_equal = true;
+                        }
+                    }
+                }
+            }
+            if (is_equal == true) {//两个状态全部项目都相等
+                StateSet.erase(state_num);
+                state_num--;
+            } else{
+                link[i][state_num] = enter;
+            }
+            //--------------------------------------------
+        }
+        i++;
+    }
+}
+
+void printState() {
+    cout << "-------------------------Status--------------------------"<<endl;
+    for(map<int, set<string>>::iterator it = StateSet.begin(); it != StateSet.end(); it++) {
+        cout << "I_" << it->first << ": ";
+        for(set<string>::iterator ij = it->second.begin(); ij != it->second.end(); ij++) {
+            cout << *ij << ", ";
+        }
+        cout << endl;
+    }
+    cout << "---------------------------------------------------------"<<endl;
+}
+
+void printLinkedTable() {
+    cout << "============================================DFA================================================"<<endl;
+    cout <<  '\t';
+    for (int i = 0; i < 11; ++i) {
+        cout << i << '\t';
+    }
+    cout << endl;
+    for (int i = 0; i < 11; ++i) {
+        cout << i << '\t';
+        for (int j = 0; j < 11; ++j) {
+            cout << link[i][j] << '\t';
+        }
+        cout << endl;
+    }
+}
+
+void getVnandVt() {
+    for(map<string, set<string>>::iterator it = productions.begin(); it != productions.end(); it++) {
+        string c = it->first;
+        if (c != "S'")
+            Vn.insert(c);
+        for(set<string>::iterator ij = it->second.begin(); ij != it->second.end(); ij++) {
+            for (int i = 0; i < (*ij).length(); ++i) {
+                if (!isVn((*ij)[i])) {
+                    Vt.insert((*ij).substr(i, 1));
+                }
+            }
+        }
+    }
+    Vt.insert("#");
+}
+
+int findIndex(string enter) {
+    int pos;
+    if (!isVn(enter[0])) {
+        for (int k = 0; k < 10; ++k) {
+            if (vt_index[k] == enter) {
+                pos = k;
+                break;
+            }
+        }
+    } else{
+        for (int k = 0; k < 10; ++k) {
+            if (vn_index[k] == enter) {
+                pos = k;
+                break;
+            }
+        }
+    }
+    return pos;
+}
+
+void GenerateAction_Table() {
+    //构造Action分析表的行名与列名
+    ActionTable[0][0] = "";
+    int j = 0;
+    set<string>::iterator ij = Vt.begin();
+    while (j < Vt.size()) {
+        vt_index[j] = *ij;
+        ij++; j++;
+    }
+
+    //构造Action表
+    // ---------移入
+    for (int i = 0; i < StateSet.size(); ++i) {
+        for (int j = 0; j < StateSet.size(); ++j) {
+            if (link[i][j].length() != 0 && (!isVn(link[i][j][0]))) {
+                string enter = link[i][j];
+                int pos = findIndex(enter);
+                ActionTable[i][pos] = "s" + to_string(j);
+            }
+        }
+    }
+    // ---------规约
+    for (int l = 0; l < StateSet.size(); ++l) {
+        if (StateSet[l].size() == 1) {
+            set<string>::iterator it = StateSet[l].begin();
+            string proj = *it;
+            if (proj == "S'->S*") {
+                ActionTable[l][findIndex("#")] = "acc";
+                continue;
+            }
+            int dot_pos = proj.find("*");
+            if (dot_pos+1 == proj.length()) {
+                string no_dot_proj = proj.erase(dot_pos,1);
+                //先找到这个项目对应的无点产生式index
+                int index = 0;//无点产生式的编号index。第几条产生式
+                for (index = 0; index < 20; ++index) {
+                    if (css_by_order[index] == no_dot_proj) {
+                        break;
+                    }
+                }
+                for (int m = 0; m < Vt.size(); ++m) {
+                    ActionTable[l][m] = "r" + to_string(index);
+                }
+            }
+        }
+    }
+    cout << endl;
+    cout << endl;
+    cout << "----------------------[Action]---------------------" << endl;
+    int m = 0;
+    cout << '\t';
+    while (vt_index[m].length() != 0) {
+        cout << vt_index[m] << '\t';
+        m++;
+    }
+    cout << endl;
+    for (int k = 0; k < StateSet.size(); ++k) {
+        cout << k << '\t';
+        for (int l = 0; l < Vt.size(); ++l) {
+            cout << ActionTable[k][l] << '\t';
+        }
+        cout <<endl;
+    }
+}
+
+void GenerateGoTo_Table() {
+
+    for(const auto& item : Vn) {
+        vn_index.push_back(item);
+    }
+
+    // 初始化GOTO表
+    for(int i = 0; i < StateSet.size(); i++) {
+        GoToTable.emplace_back();
+        for(int j = 0; i < StateSet.size(); j++){
+            GoToTable[i].emplace_back();
+        }
+    }
+
+    //构造GoTo表
+    //在link表中遍历
+    for (int i = 0; i < StateSet.size(); ++i) {
+        for (int j = 0; j < StateSet.size(); ++j) {
+            if ( link[i][j].length() != 0 && isVn(link[i][j][0]) ) {
+                string enter = link[i][j];
+                int pos = findIndex(enter);
+                GoToTable[i][pos] = j;
+            }
+        }
+    }
+    cout << endl;
+    cout << endl;
+    cout << "----------------------[GoTo]---------------------" << endl;
+    int m = 0;
+    cout << '\t';
+    while (vn_index[m].length() != 0) {
+        cout << vn_index[m] << '\t';
+        m++;
+    }
+    cout << endl;
+    for (int k = 0; k < StateSet.size(); ++k) {
+        cout << k << '\t';
+        for (int l = 0; l < Vn.size(); ++l) {
+            if (GoToTable[k][l] != 0)
+                cout << GoToTable[k][l] << '\t';
+            else
+                cout << '\t';
+        }
+        cout << endl;
+    }
+}
+
+int main() {
+    clock_t start,end;//定义clock_t变量
+    start = clock(); //开始时间
+
+    getProject();
+//    GenerateState();
+//    printState();
+//    printLinkedTable();
+//    getVnandVt();
+//    GenerateAction_Table();
+//    GenerateGoTo_Table();
+
+    //输出时间
+    end = clock();   //结束时间
+    cout << endl;
+    double times = double(end-start)/CLOCKS_PER_SEC;
+    cout<<"The Run time = "<<times<<"s" << " = " <<times * 1000 <<"ms" << endl;
+    return 0;
+}
+