编译原算符优先分析实验报告.docx

1、编译原算符优先分析实验报告学号 E10714103 专业 计算机科学与技术 姓名 万学进实验日期2010-5-25 教师签字 成绩实 验 报 告【实验名称】 算符优先文法分析【实验目的】掌握算符优先分析法的原理，利用算符优先分析法将赋值语句进行语法分析，翻译成等价的四元式表示。【实验内容】1.算术表达式的文法可以是： （1）S-#E#（2）E-E+T（3）E-T（4）T-T*F（5）T-F（6）F-PF（7）F-P（8）P-(E)（9）P-i2.根据算符优先分析法，将表达式进行语法分析，判断一个表达式是否正确。 【设计思想】（1）定义部分：定义常量、变量、数据结构。（2）初始化：设立算符优先关

2、系表、初始化变量空间（包括堆栈、结构体、数组、临时变量等）；（3）控制部分：从键盘输入一个表达式符号串；（4）利用算符优先文法分析算法进行表达式处理：根据优先关系表对表达式符号串进行堆栈（或其他）操作，输出分析结果，如果遇到错误则显示错误信息。【流程图】【源代码】#include#include#includechar Grammar2010;char VN10,VT10;char BoolArray1010;char FirstBoolArray1010;char LastBoolArray1010;char RelationShip1010;#define StackSize 100;in

3、t vtNum,vnNum;int grammarNum;int scount=0;int VNum20;int GF210;typedef struct char vt; char vn;array;typedef struct array *base; array *top; int stacksize;SqStack;typedef struct char s20; int step; char curInVt;CharType;typedef struct CharType *base; CharType *top;Stack;typedef struct int x; int y;P

4、osition;SqStack S;Stack CS;SqStack InitStack() int i,j; S.base=(array *)malloc(100*sizeof(array); if(!S.base)exit(1); S.top=S.base; S.stacksize=StackSize; array temp; printf(初始化栈：n); for(i=1;i=vnNum;i+) for(j=1;j=vtNum;j+) if(BoolArrayij=1) temp.vt=BoolArray0j; temp.vn=BoolArrayi0; *S.top=temp; S.to

5、p+; printf(%c,%cn,temp.vn,temp.vt); return S;int vNumCount() for(int i=0;i) fp=tp; continue; if(singleChar=|) Grammari+10=Grammari0; Grammarij=0; i+; j=1; continue; Grammarij=singleChar; if(singleChar=A&singleChar=Z) count=0; while(VNcount!=singleChar&VNcount!=0) count+; if(VNcount=0) VNcount=single

6、Char; vnNum=count+1; else count=0; while(VTcount!=singleChar&VTcount!=0) count+; if(VTcount=0) VTcount=singleChar; vtNum=count+1; j+; printf(输入的文法：n); for(k=0;k); printf(%c,Grammarkj); j+; printf(n); printf(vnNum:%dn,vnNum); printf(vtNum:%dn,vtNum); printf(%dnVN:,i); count=0; while(VNcount!=0) BoolA

7、rraycount+10=VNcount; LastBoolArraycount+10=VNcount; printf(%d%c ,count+1,BoolArraycount+10); count+; printf(nVT:); count=0; while(VTcount!=0) BoolArray0count+1=VTcount; LastBoolArray0count+1=VTcount; printf(%d%c ,count+1,BoolArray0count+1); count+; printf(n); fclose(fp); return i;int print() for(in

8、t i=1;i=vnNum;i+) for(int j=1;j=vtNum;j+) if(BoolArrayij=1) printf(%c %cn,BoolArrayi0,BoolArray0j); return 0;int printlast() for(int i=1;i=vnNum;i+) for(int j=1;j=vtNum;j+) if(LastBoolArrayij=1) printf(%c %cn,LastBoolArrayi0,LastBoolArray0j); return 0;int BoolArrayInitial(char vn,char vt) int row=1,

9、column=1; while(BoolArrayrow0!=vn) row+; while(BoolArray0column!=vt) column+; if(BoolArrayrowcolumn=1) return 0; BoolArrayrowcolumn=1; printf(%d %dn,row,column); return 0;int LastBoolArrayInitial(char vn,char vt) int row=1,column=1; while(LastBoolArrayrow0!=vn) row+; while(LastBoolArray0column!=vt)

10、column+; if(LastBoolArrayrowcolumn=1) return 0; LastBoolArrayrowcolumn=1; printf(%d %dn,row,column); return 0;int FirstInitial(int grammarNum) int i; for(i=0;i=grammarNum;i+) if(Grammari1Z) BoolArrayInitial(Grammari0,Grammari1); continue; if(Grammari1=A&Grammari1=Z&Grammari2!=0) if(Grammari2Z) BoolA

11、rrayInitial(Grammari0,Grammari2); printf(文法表中各行文法字符数：); vNumCount(); return 0;int LastInitial(int grammarNum) int i,count; for(i=0;i=grammarNum;i+) count=VNumi-1; if(GrammaricountZ) LastBoolArrayInitial(Grammari0,Grammaricount); continue; if(count=A&Grammaricount=Z&Grammaricount-1!=0) if(Grammaricou

12、nt-1Z) LastBoolArrayInitial(Grammari0,Grammaricount-1); printlast(); return 0;Position GetPos(array temp) for(int i=1;i=vnNum;i+) if(BoolArrayi0=temp.vn) break; for(int j=1;j=vtNum;j+) if(BoolArray0j=temp.vt) break; Position pos; pos.x=i; pos.y=j; return pos;int PrintStack() array *p=S.top,scan; sco

13、unt+; printf(scount %d:n,scount); while(p!=S.base) scan=*p; printf(%c %cn,scan.vn,scan.vt); p-; return 0;int Insert(array pushTemp) Position pos; array scan; pos=GetPos(pushTemp); if(BoolArraypos.xpos.y=0) BoolArraypos.xpos.y=1; array *p=S.base; while(p!=S.top) scan=*p; if(scan.vn=pushTemp.vn & scan

14、.vt=pushTemp.vt) break; p+; if(p=S.top) S.top+; *S.top=pushTemp; PrintStack(); return 1;int PushPop() int i; array temp,pushTemp; while(S.top!=S.base) temp=*S.top; S.top-; for(i=0;i=grammarNum;i+) if(Grammari1=temp.vn) pushTemp.vn=Grammari0; pushTemp.vt=temp.vt; Insert(pushTemp); print(); return 0;i

15、nt LastPushPop() int i,count; array temp,pushTemp; while(S.top!=S.base) temp=*S.top; S.top-; for(i=0;i=grammarNum;i+) count=VNumi-1; if(Grammaricount=temp.vn) pushTemp.vn=Grammari0; pushTemp.vt=temp.vt; Insert(pushTemp); print(); return 0;int ResetStack() int i,j; array temp; while(S.top!=S.base) S.

16、top-; printf(n); for(i=1;i=vnNum;i+) for(j=1;j=A&Grammarij=Z&(Grammarij+1Z) return 0; else return 1;Position GetOpPos(char vni,char vnj) for(int i=1;i=vtNum;i+) if(RelationShipi0=vni) break; for(int j=1;j=vtNum;j+) if(RelationShip0j=vnj) break; Position pos; pos.x=i; pos.y=j; return pos;int GetVtPos

17、(char vt) for(int i=1;i=vtNum;i+) if(LastBoolArrayi0=vt) break; return i;int RelEqual() Position pos; int j; for(int i=0;i=grammarNum;i+) j=1; while(Grammarij!=0) if(Grammarij+2=0)break; if(GrammarijZ)&(Grammarij+2Z) pos=GetOpPos(Grammarij,Grammarij+2); RelationShippos.xpos.y=;/2表示= j+; return 0;int

18、 RelShBlanket() int row; Position pos; int i,j; for(i=1;i=vtNum;i+) RelationShipi0=BoolArray0i; RelationShip0i=BoolArray0i; for(i=0;i=grammarNum;i+) j=1; while(Grammarij!=0) if(Judge(i,j)=-1)break; if(Judge(i,j)=0) row=GetVtPos(Grammarij); for(int ii=1;ii;/3表示大于 if(Judge(i,j)=1) row=GetVtPos(Grammar

19、ij+1); for(int ii=1;ii=9;ii+) if(FirstBoolArrayrowii=1) pos=GetOpPos(Grammarij,FirstBoolArray0ii); RelationShippos.xpos.y=;/1表示小于 j+; RelEqual(); printf(表达式文法算符优先关系表：n); RelationShip00= ; for(i=0;i=vtNum;i+) for(int j=0;j=vtNum;j+) if(RelationShipij=0) RelationShipij=0; printf(%4c ,RelationShipij); printf(n); return 0;int ChangeValue() int change=0; int i,j; for(i=1;i=vtNum;i+) for(j=1;j) if(GF0i=GF1j) GF0i=GF1j+1; change=1; if(RelationShipij=GF1j) GF1j=GF0i+1; change=1; if(RelationShipij=) if(GF0i!=GF1j) if(GF0iGF1j) GF1j=GF0i; change=1; if(GF0iGF1j) GF0i=GF1j; change=1; if(change=1)