1、include<stdio.h>include<malloc.h>include<conio.h>definemaxsize100typedefdoubledatatype1;typedefchardatatype2;typedefstructstack1datatype1data1maxsize;inttop1;/*棧頂元素*/seqstack1,*pseqstack1;/*順序棧*/typedefstructstack2datatype2data2maxsize;inttop2;/*棧頂元素*/seqstack2,*pseqstack2;/*順序棧*/*

2、棧的初始化*/pseqstack1init_seqstack1(void)pseqstack1S;S=(pseqstack1)malloc(sizeof(pseqstack1);if(S)S->top1=-1;returnS;pseqstack2init_seqstack2(void)pseqstack2S;S=(pseqstack2)malloc(sizeof(pseqstack2);if(S)S->top2=-1;returnS;/*判斷?？?/intempty_seqstack1(pseqstack1S)if(S->top1=-1)return1;intempty_se

3、qstack2(pseqstack2S)(if(S->top2=-1)return1;elsereturn0;/*X入棧*/intpush_seqstack1(pseqstack1S,datatype1X)(if(S->top1=maxsize-1)(printf("棧滿，無法入棧！n");return0;else(S->top1+;S->data1S->top1=X;return1;intpush_seqstack2(pseqstack2S,datatype2X)(if(S->top2=maxsize-1)(printf("棧

4、滿，無法入棧！n");return0;else(S->top2+;S->data2S->top2=X;return1;/*X出棧*/intpop_seqstack1(pseqstack1S,datatype1*X)(if(empty_seqstack1(S)return0;else(*X=S->data1S->top1;S->top1-;return1;intpop_seqstack2(pseqstack2S,datatype2*X)(if(empty_seqstack2(S)return0;else(*X=S->data2S->top

5、2;S->top2-;return1;/*求棧頂元素*/intgettop_seqstack1(pseqstack1S,datatype1*X)(if(empty_seqstack1(S)return0;else*X=S->data1S->top1;return1;intgettop_seqstack2(pseqstack2S,datatype2*X)(if(empty_seqstack2(S)return0;else*X=S->data2S->top2;return1;/*判斷字符是否為操作數。若是返回1,否則返回0*/intisnum(charc)(if(c&

6、gt;='0'&&c<='9')return1;/*求后綴表達式的值*/doublepostfix_exp(char*A)(pseqstack1S;/*定義棧S*/doubleoperand=0;doubleresult;/*存放棧頂元素*/doublea;/*運算符ch前的操作數出棧存入a*/doubleb;/*運算符ch后的操作數出棧存入b*/doublec;/*c=achb*/charch;/*存放讀取到的表達式(A)的字符*/ch=*A+;/*讀表達式字符=>A*/S=init_seqstack1();/*初始化棧*/whil

7、e(ch!='#')/*遇到元素！='#'時*/(if(isnum(ch)/*判斷ch是否為數字字符，計算出操作數*/operand=operand*10+(ch-'0');else/*否則*/(if(operand)(push_seqstack1(S,operand);/*當前字符不是數字，操作數結束，要入棧*/operand=0;if(ch!=''&&ch!='')(pop_seqstack1(S,&b);/*運算符ch后的操作數出棧存入b*/pop_seqstack1(S,&a

8、);/*運算符ch前的操作數出棧存入a*/switch(ch)/*求achb=?，將結果賦給c*/(case'+':c=a+b;break;case'-':c=a-b;break;casec=a*b;break;case'/':if(b!=0)c=a/b;printf(-分母為零!");push_seqstack1(S,c);/*將c壓入棧中*/ch=*A+;/*指針向下移動一位*/*遇到'#'循環結束*/gettop_seqstack1(S,&result);/*此時棧頂元素即為計算結果result*/retu

9、rnresult;/*優先級判斷函數*/intpriority(charop)switch(op)case'#':return1;case')':return2;case'+':case'-':return3;case'*':case'/':return4;case'(':return5;default:return0;/*將指針infixexp指向的中綴表達式轉換為指針postfixexp指向的后綴表達式*/intinfix_exp_value(char*infixexp,char

10、*postfixexp)pseqstack2S;/*定義棧S*/intcount=0;charw;/*存放讀取到的表達式(infixexp)的字符*/charc;/*存放棧頂元素*/chartopelement;/*存出棧元素*/S=init_seqstack2();/*初始化棧*/if(!S)/*棧的初始化判斷*/printf("棧初始化失敗!");return0;push_seqstack2(S,'#');/*將結束符'#'加入運算符棧S中*/w=*infixexp;/*讀表達式字符=>w*/while(gettop_seqstac

11、k2(S,&c),c)!='#'|w!='#')/*<3>棧頂元素不等于'#'或w不等于'#'時循環*/(if(isnum(w)/*判斷w是否為操作數，若是直接輸出，讀下一個字符=>w，轉<3>*/(if(count)(*postfixexp=''postfixexp+;count=0;*postfixexp=w;postfixexp+;w=*(+infixexp);else/*w若是運算符分類如下*/(count=1;if(gettop_seqstack2(S,&c)

12、,c)='('&&w=')')/*如果棧頂為'('并且w為')'則,('出棧不輸出，讀下一個字符=>w,轉<3>*/(pop_seqstack2(S,&topelement);/*將'('出棧存入topelement*/w=*(+infixexp);elseif(gettop_seqstack2(S,&c),c)='('|priority(gettop_seqstack2(S,&c),c)<priority(w)/*如果棧頂為&

13、#39;('或者棧頂優先級小于w優先級，則w入棧,讀下一個字符=>w,轉<3>*/(push_seqstack2(S,w);w=*(+infixexp);else/*否則*/*從運算符棧中出棧并輸出，轉<3>*/(pop_seqstack2(S,&topelement);*postfixexp=topelement;postfixexp+;*postfixexp='#'/*在指針postfixexp指向的后綴表達式結尾追加字符'#'*/*(+postfixexp)='0'/*在指針postfixexp指向的后綴表達式最后追加結束符'0'*/return1;/*主函數*/intmain()(inti=0;charAmaxsize;charBmaxsize;printf("請輸入表達式，如:20+13#，必須以#結尾!n");/*1+2*(9+7)-4/2#23+(12*3-2)/4+34*5/7)+10