编译原理——简单计算器的编译器的设计与实现 Calculator(终).rar

#include<iostream> #include<string> #include<vector> #include<iomanip> #include <stack> #include <map> using namespace std; //*********************词法分析器******************************// char SEPARATER[2] = { '(', ')' }; //分隔符 char OPERATOR[5] = { '+', '-', '*', '/', '=' }; //运算符 char FILTER[4] = { ' ', '\t', '\r', '\n' }; //过滤符 /**判断是否为分隔符**/ bool IsSeparater(char ch){ for (int i = 0; i<2; i++){ if (SEPARATER[i] == ch){ return true; } } return false; } /**判断是否为运算符**/ bool IsOperator(char ch){ for (int i = 0; i<5; i++){ if (OPERATOR[i] == ch){ return true; } } return false; } /**判断是否为过滤符**/ bool IsFilter(char ch){ for (int i = 0; i<4; i++){ if (FILTER[i] == ch){ return true; } } return false; } /**判断是否为数字**/ bool IsDigit(char ch){ if (ch >= '0' && ch <= '9') return true; return false; } /**词法分析**/ vector<string> analyse(string expression){ vector<string> vec; char ch = ' '; for (int i = 0; i < expression.length(); i++) { string arr = ""; ch = expression[i]; if (IsFilter(ch)){} //判断是否为过滤符 else if (IsDigit(ch)){ //判断是否为数字 while (IsDigit(ch) || IsFilter(ch)){ if (IsDigit(ch)) arr += ch; i++; ch = expression[i]; } i--; //printf("%3d ", CONSTANT); cout << "\t\t\t< 整形数 , " << arr <<">"<< endl; vec.push_back(arr); } else if (IsOperator(ch)) { arr += ch; //printf("%3d ", value(OPERATOR, 8, *arr.data())); cout << "\t\t\t< 运算符 , " << arr << ">" << endl; vec.push_back(arr); } else if (IsSeparater(ch)) { arr += ch; //printf("%3d ", value(SEPARATER, 8, *arr.data())); cout << "\t\t\t< 分隔符 , " << arr << ">" << endl; vec.push_back(arr); } else { cout << "\t\t\t\"" << ch << "\":无法识别的字符！" << endl; vec.clear(); return vec; } } return vec; } //*********************中间代码生成器******************************// string InversePolish(string s_mid) { string s_beh = ""; stack<char> stk; map<char, int> op;//利用map来实现运算符对应其优先级 op['('] = 0; op[')'] = 0; op['+'] = 1; op['-'] = 1; op['*'] = 2; op['/'] = 2; string::iterator it = s_mid.begin();; while (it != s_mid.end()) { if (op.count(*it))//判断该元素是否为运算符 { if (*it == ')')//若为’）‘，把栈中的运算符依次加入后缀表达式，直到出现'（'，’（‘出栈，退出该次循环 { while (stk.top() != '(') { s_beh += stk.top(); s_beh += " "; stk.pop(); } stk.pop(); } else if (stk.empty() || *it == '(' || op[*it]>op[stk.top()])//若为‘（’，入栈 ; 要入栈的运算符优先级大于等于栈顶的运算符的优先级，直接入栈 { stk.push(*it); } else if (op[*it] <= op[stk.top()])// 入栈的运算符优先级小于等于栈顶的运算符的优先级，栈顶运算符出栈，再次比较，直到出现优先级低的运算符，或者栈为空，退出 { while (op[*it] <= op[stk.top()] && (!stk.empty())) { s_beh += stk.top(); s_beh += " "; stk.pop(); if (stk.empty()) break; } stk.push(*it); } } else { s_beh += *it; it++; if (it != s_mid.end() && op.count(*it)) s_beh += " "; it--; } it++; if (it == s_mid.end())//当中缀表达式输出完成，所有元素出栈 { while (!stk.empty()) { s_beh += " "; s_beh += stk.top(); stk.pop(); } break; } } cout <<"逆波兰表达式："<< s_beh << endl; return s_beh; } //*********************后缀表达式计算******************************// int Op(int a, char op, int b) { switch (op) { case '+':return a + b; break; case '-':return a - b; break; case '*':return a*b; break; case '/':return a / b; break; } } int calculate(char *str) { stack<int> s;//暂存操作数 int i = 0; int offset = 0; int flag = 0; int Length = strlen(str); int Result; while (i < Length) { string One = ""; for (i; i < Length; i++) { One += str[i]; if (((str[i] == ' ')&&(str[i+1]!=' ')) || (i == Length - 1)) { char* OneNumber = (char*)One.data(); int Number = atoi(One.c_str()); if (IsOperator(*OneNumber)) { Number = 0; } s.push(Number); if (IsOperator(*OneNumber)) { s.pop(); int x = s.top(); s.pop(); int y = s.top(); s.pop(); Result = Op(y, *OneNumber, x); s.push(Result); } offset = i + 1; break; } } i = offset; } return s.top(); } //*********************语法分析器******************************// //Action表 int action[16][8] = { { 0, 0, 0, 0, 4, 0, 5, 0 },//0 { 6, 7, 0, 0, 0, 0, 0, 100 },//1 { -3, -3, 8, 9, 0, -3, 0, -3 },//2 { -6, -6, -6, -6, 0, -6, 0, -6 },//3 { 0, 0, 0, 0, 4, 0, 5, 0 },//4 { -8, -8, -8, -8, 0, -8, 0, -8 },//5 { 0, 0, 0, 0, 4, 0, 5, 0 },//6 { 0, 0, 0, 0, 4, 0, 5, 0 },//7 { 0, 0, 0, 0, 4, 0, 5, 0 },//8 { 0, 0, 0, 0, 4, 0, 5, 0 },//9 { 6, 7, 0, 0, 0, 15, 0, 0 },//10 { -1, -1, 8, 9, 0, -1, 0, -1 },//11 { -2, -2, 8, 9, 0, -2, 0, -2 },//12 { -4, -4, -4, -4, 0, -4, 0, -4 },//13 { -5, -5, -5, -5, 0, -5, 0, -5 },//14 { -7, -7, -7, -7, 0, -7, 0, -7 }//15 };//17 //Goto表 int gotol[16][3] = { { 1, 2, 3 },//0 { 0, 0, 0 },//1 { 0, 0, 0 },//2 { 0, 0, 0 },//3 { 10, 2, 3 },//4 { 0, 0, 0 },//5 { 0, 11, 3 },//6 { 0, 12, 3 },//7 { 0, 0, 13 },//8 { 0, 0,14 },//9 { 0, 0, 0 },//10 { 0, 0, 0 },//11 { 0, 0, 0 },//12 { 0, 0, 0 },//13 { 0, 0, 0 },//14 { 0, 0, 0 } };//17 //终结符集合 string endls[9] = { "+", "-", "*", "/", "(", ")", "=","id","#" }; //非终结符集合 string noends[3] = { "E", "T", "F" }; //产生式集合 string products[9] = { "E", "E+T", "E-T", "T", "T*F", "T/F", "F", "(E)", "id" }; /* E=> T+F | T-F |T T=> F*T | F/T |F F=> (E) | id */ //状态栈 class statestack { private: int *base;//栈底指针 int *top;//栈顶指针 int size;//栈内元素个数 int stacksize;//栈的大小 public: statestack() { size = 0; stacksize = 20; base = new int[stacksize]; top = base; } int getTop()//获取栈顶的元素。 { if (base == top) { return -1; } else { return *(top - 1); } } bool statePush(int elem)//元素入栈 { ++size; (*top) = elem; ++top; return true; } void statePop(int time)//元素出栈 { for (int i = 0; i<time; i++) { --top; --size; } } void printState()//输出栈内的所有元素 { string str = " "; int *pre; for (pre = base; pre<top; pre++) { if (*pre>9) // 栈中保存的10转换成1、0 { char ch1 = (*pre / 10) + 48; char ch2 = (*pre % 10) + 48; str += ch1; str += ch2; } else { char ch = *pre + 48; str += ch; } } cout << setw(15) << setiosflags(ios_base::left) << str; } }; //符号栈 class symbolstack { private: string *base; string *top; int size; int stacksize; public: symbolstack() { size = 0; stacksize = 20; base = new string[stacksize]; top = base; } string getTop()//获取栈顶的元素。 { if (base == top) { return ""; } else { return *(top - 1); } } //元素入栈 bool symbolPush(string elem) { ++size; *top = elem; ++top; return true; } //元素出栈 void symbolPop(int time) { for (int i = 0; i<time; i++) { --top; --size; } } //输出栈内的所有元素 void printSymbol() { string str = ""; string *pre; for (pre = base; pre<top; pre++) { str += *pre; } cout << setw(15) << setiosflags(ios_base::left) << str; } }; class analyseLR { private: int step; string inputstr;//布尔表达式 statestack state;//状态栈 symbolstack symbol;//符号栈 statestack data;//数据栈 //vector<string> fors;//四元式 public: //构造函数 analyseLR() { step = 0; inputstr = ""; state = statestack(); symbol = symbolstack();