数据结构课程设计之算术表达式求值

..1[实验题目及要求][问题描述]一个算术表达式是由操作数<operand>、运算符<operator>和界限符<delimiter>组成的。假设操作数是正实数,运算符只含加减乘除等四种运算符,界限符有左右括号和表达式起始、结束符"#",如：#〔7+15*〔23-28/4#。引入表达式起始、结束符是为了方便。编程利用"算符优先法"求算术表达式的值。[基本要求]〔1从键盘或文件读入一个合法的算术表达式,输出正确的结果。〔2显示输入序列和栈的变化过程。〔3考虑算法的健壮性,当表达式错误时,要给出错误原因的提示。<4>实现非整数的处理〔可选功能。2[源代码〔C语言]#include<stdio.h>#include<stdlib.h>#include<string.h>#defineMAXSIZE20#defineOK1#defineERROR0#defineOVERLOW0#defineYES1#defineNO0typedefstruct{char*base;char*top;intstacksize; //最大存储量}OPTR; //字符存储栈typedefstruct{float*base;float*top;intstacksize; //最大存储量}OPND; //数值存储栈intInitOptrStack<OPTR*>; //字符栈初始化函数intOptrPush<OPTR*,char>; //进字符栈操作intOptrPop<OPTR*,char*>; //出字符栈操作intOptrEmpty<OPTR>; //判断字符栈是否为空charGetOptrTop<OPTR>; //返回字符栈顶元素intInitOpndStack<OPND*>; //数值栈初始化函数intOpndPush<OPND*,float>; //进数值栈操作intOpndPop<OPND*,float*>; //出数值栈操作intOpndEmpty<OPND>; //判断数值栈是否为空intJudgeChar<char>; //判断是否为字符floatGetFloat<char*>; //接收一个数字charPrecede<char,char>; //判断优先级操作floatCaculate<float,float,char>;//计算数值voidmain<>{charch,noMean,ci;floatnum,number1,number2;OPTRoptr;OPNDopnd;//system<"color30">; InitOptrStack<&optr>; InitOpndStack<&opnd>;while<1>{ printf<" 请输入表达式以"#"开始,以"#"结束\n ">;do{ ch=getchar<>; }while<ch!='#'>; //忽略前面非‘#’字符 OptrPush<&optr,ch>; ch=getchar<>;while<ch!='#'||GetOptrTop<optr>!='#'>{if<!JudgeChar<ch>>{ //如果输入的是数字 num=GetFloat<&ch>; OpndPush<&opnd,num>; }else{ //输入的是字符switch<Precede<GetOptrTop<optr>,ch>>{case'<': OptrPush<&optr,ch>; //栈顶优先级低 ch=getchar<>;break;case'=': OptrPop<&optr,&noMean>; //左右括号,把左括号出栈 ch=getchar<>;break;case'>': //栈顶优先级高if<OpndPop<&opnd,&number2>&&OpndPop<&opnd,&number1>>{ OptrPop<&optr,&ci>; num=Caculate<number1,number2,ci>; //出栈计算 OpndPush<&opnd,num>; }else{ printf<" 输入过多运算符！\n">; system<"PAUSE">; exit<0>; }break; }//witch }//else }if<opnd.top-opnd.base>=2>{ printf<" 俩个括号之间缺少运算符！\n ">; system<"PAUSE">; exit<0>; } OpndPop<&opnd,&num>; //直接把OPND的栈元素赋值给num printf<" 运算结果为%.3f\n",num>; } system<"PAUSE">;}intInitOptrStack<OPTR*OP>{OP->base=<char*>malloc<<MAXSIZE+1>*sizeof<char>>;OP->top=OP->base;OP->stacksize=MAXSIZE;returnOK;}intOptrPush<OPTR*OP,charch>{ *<OP->top>=ch;OP->top++;returnOK;}intOptrPop<OPTR*OP,char*ch>{if<OP->base==OP->top>returnERROR;else{OP->top--; *ch=*<OP->top>;returnOK; }}intOptrEmpty<OPTROP>{if<OP.top==OP.base>returnYES;elsereturnNO;}charGetOptrTop<OPTROP>{return*<OP.top-1>;}intInitOpndStack<OPND*OP>{if<!<OP->base=<float*>malloc<<MAXSIZE+1>*sizeof<float>>>> exit<OVERLOW>;OP->top=OP->base;OP->stacksize=MAXSIZE;returnOK;}intOpndPush<OPND*OP,floatnumber>{ *<OP->top>=number;OP->top++;returnOK;}intOpndPop<OPND*OP,float*number>{if<OP->top==OP->base>returnERROR;else{OP->top--; *number=*<OP->top>;returnOK; }}intOpndEmpty<OPNDOP>{if<OP.top==OP.base>returnYES;elsereturnNO;}intJudgeChar<charch>{if<ch>='0'&&ch<='9'>returnNO;elsereturnYES;}floatGetFloat<char*ch>{inti;floatnum=0;for<i=0;*ch>='0'&&*ch<='9';i++>{ num=num*10+*ch-'0'; *ch=getchar<>; }returnnum;}charPrecede<chara,charb>{charch;switch<a>{case'+': case'-': if<b=='*'||b=='/'||b=='<'> ch='<';else ch='>';break;case'*':case'/': if<b=='<'> ch='<';else ch='>';break;case'<': if<b=='>'> ch='=';elseif<b=='#'>{ printf<" 缺少反括号\n">; system<"PAUSE">; exit<0>; }else ch='<';break;case'>': if<b=='<'>{ printf<" 两个括号之间没有符号相连！\n">; system<"PAUSE">; exit<0>; } ch='>';break;case'#': if<b=='#'> ch='=';elseif<b=='>'>{ printf<" 没有左括号！\n ">; system<"PAUSE">; exit<0>; }else ch='<';break;default: printf<" 输入运算符超出范围! \n ">; system<"PAUSE">; exit<0>;break; }returnch;}floatCaculate<floatnumber1,floatnumber2,charci>{floatnum;switch<ci>{case'+': num=number1+number2; break;case'-': num=number1-number2; break;case'*': num=number1*number2; break;case'/': num=number1/number2; break; }returnnum;}3[算法思想]根据栈的原理,建立数字栈OPND和运算符号栈OPTR,对读入的字符进行判断,存入不同的栈内,每次读入一个字符就把该字符和运算符栈顶的优先级进行比较,然后选择相应的操作,这是这个程序的核心代码,如下：switch<Precede<GetOptrTop<optr>,ch>>{ case'<': OptrPush<&optr,ch>; //栈顶优先级低 ch=getchar<>; break; case'=': OptrPop<&optr,&noMean>; //左右括号,把左括号出栈 ch=getchar<>; break; case'>': //栈顶优先级高 if<OpndPop<&opnd,&number2>&&OpndPop<&opnd,&number1>>{ OptrPop<&optr,&ci>; num=Caculate<number1,number2,ci>; //出栈计算 OpndPush<&opnd,num>; }else{