《C高級編程》源代碼的進

1、/*程序名稱:表達式計算器編譯環(huán)境:Microsoft Visual C+ 6.0時間:200801*/*說明:采用樹形結(jié)構(gòu)處理表達式,按優(yōu)先級運算結(jié)果,一個加,減,乘,除或數(shù)值為一個節(jié)點優(yōu)先級如下:函數(shù):4括號:3乘除:2加減:1*/#include <windows.h>#include <iostream>#include <fstream>#include <string>#include <cmath>using namespace std;const char NUM='0','1',

2、9;2','3','4','5','6','7','8','9','.'const char OPERATION='+','-','*','/'const double PI=3.14159265358979;const double EE=2.71828182818281;class Fun /處理系統(tǒng)數(shù)學(xué)函數(shù)的類public:Fun(string o,int t,double l=0.0,do

3、uble r=0.0):op(o),type(t),lvalue(l),rvalue(r)static string FUN;double calc();private:int type; /666 0 1 sin90 2 3! 3 3C2 string op; /函數(shù)類型double lvalue; /函數(shù)左邊的值double rvalue; /函數(shù)右邊的值static int FunNum;int Fun:FunNum=10;string Fun:FUN="!","sin","cos","tan","

4、log","ln","C","A","","-"/*函數(shù)說明:1:log是以10為底的工程對數(shù)2:ln 是以e為底的自然對數(shù)3:C 計算組合數(shù) 輸入規(guī)則 如計算 3取2的組合 輸入表達式 3C24:A 計算排列數(shù) 輸入規(guī)則 如計算 3取2的排列 輸入表達式 3A25:! 計算階乘6: x的y次方 輸入 xy*/int factorial(int n) /階乘函數(shù)int i,s=1;for(i=1;i<=n;i+)s*=i;return s;int C(int a,int b)re

5、turn factorial(a)/(factorial(b)*factorial(a-b);int A(int a,int b)return factorial(a)/factorial(b);double Fun:calc() /計算系統(tǒng)函數(shù)的值if(type=0)return lvalue;elseif(op="!")return factorial(lvalue);if(op="sin")return sin(rvalue/180*PI);if(op="cos")return cos(rvalue/180*PI);if(op=

6、"tan")return tan(rvalue/180*PI);if(op="log")return log10(rvalue);if(op="ln")return log10(rvalue)/log10(EE);if(op="C")return C(lvalue,rvalue);if(op="A")return A(lvalue,rvalue);if(op="")return pow(lvalue,rvalue);if(op="-")return -rv

7、alue;elsestring err="暫時沒有函數(shù)"+op;MessageBox(NULL,err.c_str(),"錯誤",MB_OK);return 0;struct Unit /雙向鏈表保存運算單元Unit(int p,char o,string c,double v,int t,Unit * pr=NULL,Unit * n=NULL):PRI(p),Operation(o),Code(c),value(v),Type(t),Pre(pr),Next(n)int PRI; /優(yōu)先級char Operation; /操作符string Code

8、; /原始代碼double value; /數(shù)據(jù)int Type; /類型 操作符0 數(shù)據(jù)1 函數(shù)2Unit * Pre; /構(gòu)成雙向鏈表Unit * Next;class Node /表達式樹狀結(jié)構(gòu)的節(jié)點public:Node(char o,int p,int e=1,double v=0,Node * ph=NULL,Node * pl=NULL,Node * pr=NULL):Operation(o),PRI(p),Expression(e),value(v),Head(ph),Left(pl),Right(pr)Node * Head; /節(jié)點的根,左樹枝,右樹枝Node * Left

9、;Node * Right;double GetValue();char GetOperation() const return Operation;int GetPri() const return PRI;int IsExp() const return Expression;private:char Operation; /操作符int PRI; /優(yōu)先級int Expression; /記錄該節(jié)點是否是表達式0 1double value; /該節(jié)點的值;double Node:GetValue() /運算該節(jié)點的值if(IsExp() /該節(jié)點的值還未算出來double lvalue

10、,rvalue;lvalue=Left->GetValue();rvalue=Right->GetValue();Expression=0;char op=GetOperation();switch(op)case '+':return lvalue+rvalue;case '-':return lvalue-rvalue;case '*':return lvalue*rvalue;case '/':return lvalue/rvalue;default:return 0;elsereturn value;bool

11、Isnum(char c)for(int i=0;i<sizeof(NUM);i+)if(c=NUMi)return true;return false;bool Isoperation(char c)for(int i=0;i<sizeof(OPERATION);i+)if(c=OPERATIONi)return true;return false;Unit * Analyse(string exp) /分析表達式并生成鏈表int pri=0; /當前優(yōu)先級int stat=1; /當前的讀入狀態(tài) 括號 0 運算符 1 其他 2Unit * head=NULL,* p=NULL;

12、int i=0,explen;explen=exp.size();for(i=0;i<explen;i+)char c=exp.at(i);if(c='(')pri+=3;stat=0;else if(c=')')pri-=3;stat=0;else if(Isoperation(c) && stat!=1) /操作符后的當正負號處理stat=1;Unit * temp=p;int add_pri; /自身增加的優(yōu)先級if(c='+' | c='-')add_pri=1;elseadd_pri=2;p->

13、;Next=new Unit(pri+add_pri,c," ",0,0);p=p->Next;p->Pre=temp;else /其他的當做函數(shù)處理stat=2;string function=""while(i<explen && (c=exp.at(i),! Isoperation(c) && c!=')')function+=c;i+;i-;if(head=NULL)p=new Unit(pri,' ',function,0,2);head=p;elseUnit *

14、 temp=p;p->Next=new Unit(pri,' ',function,0,2);p=p->Next;p->Pre=temp;return head;Unit * Calc(Unit * head) /計算雙向鏈表基本單元的值Unit * p=head;while(p!=NULL)if(p->Type!=0) /非操作符string temp=p->Code;string op;double lvalue=0,rvalue=0;int l_point=0,r_point=0;int i=0,type=0;char ch;while(i&

15、lt;temp.size() && (ch=temp.at(i),Isnum(ch)if(ch='.')l_point+;i+;continue;if(! l_point)lvalue*=10;lvalue+=(ch-'0')*pow(10,-l_point);i+;if(l_point)l_point+;while(i<temp.size() && (ch=temp.at(i),! Isnum(ch)op+=ch;type=1;i+;while(i<temp.size() && (ch=temp.at

16、(i),Isnum(ch)if(ch='.')r_point+;i+;continue;if(! r_point)rvalue*=10;rvalue+=(ch-'0')*pow(10,-r_point);i+;if(r_point)r_point+;Fun * f=new Fun(op,type,lvalue,rvalue);p->value=f->calc();p=p->Next;return head;Node * Tree(Unit * head) /生成表達式樹Node * root=NULL,* proot=NULL,* pbranc

17、h=NULL;Unit * p=head;int now_pri; /當前優(yōu)先級bool hadop=false;while(p!=NULL)if(p->Type=0) /如果是一個操作符hadop=true;if(root=NULL)proot=new Node(p->Operation,p->PRI,1);root=proot;pbranch=root;now_pri=p->PRI;proot->Left=new Node(' ',0,0,p->Pre->value);proot->Right=new Node(' &

18、#39;,0,0,p->Next->value);elseif(p->PRI<now_pri) /優(yōu)先級低于當前優(yōu)先級,樹根方向proot=new Node(p->Operation,p->PRI,1); /新的樹根proot->Left=root; /根的變換proot->Left->Head=proot;proot->Right=new Node(' ',0,0,p->Next->value);proot->Right->Head=proot;root=proot;pbranch=proot

19、; /右樹枝的變換/pbranch->Right=new Node(' ',0,0,p->Pre->value); /樹枝右邊取值else if(p->PRI=now_pri) /優(yōu)先級相同,先算左邊的Node * temp;temp=new Node(p->Operation,p->PRI,1);temp->Left=pbranch;if(pbranch->Head=NULL)proot=temp;root=proot;pbranch->Head=proot;elseNode * temp0;temp0=pbranch-&

20、gt;Head;temp0->Right=temp;temp->Head=temp0;pbranch->Head=temp;pbranch=temp;pbranch->Right=new Node(' ',0,0,p->Next->value);pbranch->Right->Head=pbranch;elseNode * temp;temp=new Node(p->Operation,p->PRI,1);pbranch->Right=temp;temp->Head=pbranch;pbranch=pbranch->Right;pbranch->Left=new Node(' ',0,0,p->Pre->value);pbranch->Left->Head=pbranch;pbranch->Right=new Node(' ',0,0,p->Next->value);pbranch->Right-&