编译技术课程LL1文法分析器.doc

实验 三 LL(1)文法预测分析模拟实验目的：编写程序完成一个LL（1）文法的预测分析过程实验内容： 1. 给定一个文法，如教材P94ETEE+TE| TFTT*FT|Fi|(E)2. 构造预测分析表，将教材P95的表5.3存储与二维数组中3. 设置分析栈，编写程序实现P95的表5.4的分析过程#include#include#include#define LINE 5 #define ROW 8char AnalStack20; /分析栈 char SpareStack20; /剩余栈 char TerSymbol20 = i, +, -, *, /, (, ), # ;/终结符 char NTerSymbol20 = E,D,T,B,F; /非终结符 int j = 0, b = 0,l = 0 ,top = 0; typedef struct LLType char nonchar; /非终结符 char production5; /产生式 int length; /产生式长度 LL1Type; LL1Type e, d, d1 , t, c, c1 , f, f1;LL1Type PreTableLINEROW; void print() int a; for (a = 0; a = top + 1; +a) printf(%c, AnalStacka); printf(tt); void print1() int j; for(j = 0; j b; +j) printf( ); for (j = b; j l; +j) printf(%c, SpareStackj); printf(ttt); int main() int m, n, k = 1, flag = 0, finish = 0; char ch, x; LL1Type str;e.nonchar = E; strcpy(duction, TD); /ETE e.length = 2; d.nonchar = D; strcpy(duction, +TD);/E+TE d.length = 3; /d1.nonchar = D; /strcpy(duction, -TD);/D-TD /d1.length = 3; d1.nonchar = D; strcpy(duction, .); /E d1.length = 1; t.nonchar = T; strcpy(duction, FB);/TFTt.length = 2; c.nonchar = B; strcpy(duction, *FB);/B*FT c.length = 3; /c1.nonchar = B; /strcpy(duction, /FB);/B/FB /c1.length = 3;c1.nonchar = B; strcpy(duction, .);/T c1.length = 1; f.nonchar = F; strcpy(duction, (E);/F(E) f.length = 3; f1.nonchar = F; strcpy(duction, i);/Fif1.length = 1; for (m = 0; m LINE; m+)/初始化预测分析表 for (n = 0; n ROW; n+) PreTablemn.nonchar = N; /填充预测分析表 PreTable00 = e; PreTable05 = e; PreTable11 = d; /PreTable12 = d1; PreTable16 = d1; PreTable17 = d1; PreTable20 = t; PreTable25 = t; PreTable31 = c1; PreTable32 = c1; PreTable33 = c; /PreTable34 = c1; PreTable36 = c1; PreTable37 = c1; PreTable40 = f1; PreTable45 = f; printf(Please Enter A String to analyze:); do /读入分析串，放入剩余栈中 scanf(%c, &ch); if (ch!=i & ch!=+ & ch!=- & ch!=* & ch!=/ & ch!=( & ch!=) & ch!=#) printf(Input characters are illegal!n); exit(1); SpareStackj = ch; j+; while (ch!=#); l = j;/分析串长度 ch = SpareStack0;/当前分析字符 AnalStacktop= #; AnalStack+top = E;/#,E进栈 printf(nSteptAnalysis stacktRemaining stringtProductionn); do x = AnalStacktop-; /为当前栈顶字符printf(%dt, k+); for (j = 0; j ROW; j+) /判断是否为终结符 if (x = TerSymbolj) flag = 1; break; if (flag = 1) /如果是终结符 if (x = #) print(); print1(); finish = 1; /结束标记 printf(Accept!n); getchar(); exit(1); if (x = ch) print(); print1(); printf(%c matchingn, ch); ch = SpareStack+b; /下一个输入字符 flag = 0; /恢复标记 else/出错处理 print(); print1(); printf(%c Error!n, ch);/输出出错终结符 exit(1); else/非终结符处理 for (j = 0; j LINE; j+) if (x = NTerSymbolj) m = j; break; for (j = 0; j , str.nonchar);/输出产生式左边字符 for (j = 0; j = 0; j-)/产生式逆序入栈 AnalStack+top = ductio