高手帮忙作一道题呗
输入一数学表达式的字符串,输出该表达式值(不考虑先乘除后加减).例:输入:2*3+4/5-6 输出:-4高手可一定要露脸啊!
2010-12-01 15:43
2010-12-01 15:44
2010-12-01 16:57
2010-12-03 12:17
2010-12-08 10:11
2010-12-08 10:14
程序代码：
#include<iostream.h>
typedef struct
{
int num[10];
int top;
}numStack;
typedef struct
{
char ch[10];
int top;
}charStack;
void InitnStack(numStack &ns)
{
ns.top=-1;
}
void InitcStack(charStack &cs)
{
cs.top=0;
cs.ch[0]='#';
}
bool iscEmpty(charStack cs)
{
if(cs.top==0)return true;
else return false;
}
void numPush(numStack &ns,int n)
{
ns.top++;
ns.num[ns.top]=n;
}
void charPush(charStack &cs,char n)
{
cs.top++;
cs.ch[cs.top]=n;
}
int numPop(numStack &ns)
{
ns.top--;
return ns.num[ns.top+1];
}
char charPop(charStack &cs)
{
cs.top--;
return cs.ch[cs.top+1];
}
int getnTop(numStack ns)
{
return ns.num[ns.top];
}
char getcTop(charStack cs)
{
return cs.ch[cs.top];
}
int IsChar(char c)
{
switch(c)
{
case '+':return 1;break;
case '-':return 2;break;
case '*':return 3;break;
case '/':return 4;break;
case '#':return 5;break;
case '(':return 6;break;
case ')':return 7;break;
default:return 0;break;
}
}
int IsNum(char c)
{
switch(c)
{
case '0':return 0;
case '1':return 1;
case '2':return 2;
case '3':return 3;
case '4':return 4;
case '5':return 5;
case '6':return 6;
case '7':return 7;
case '8':return 8;
case '9':return 9;
default:return 10;
}
}
bool translate(char s[],numStack &ns,charStack &cs)
{
int i=0,m,n;
InitnStack(ns);
InitcStack(cs);
while(s[i]!='\0')
{
switch(IsChar(s[i]))
{
case 7:
{
while(getcTop(cs)!='(')
{
switch(IsChar(charPop(cs)))
{
case 1:m=numPop(ns);n=numPop(ns);numPush(ns,n+m);break;
case 2:m=numPop(ns);n=numPop(ns);numPush(ns,n-m);break;
case 3:m=numPop(ns);n=numPop(ns);numPush(ns,n*m);break;
case 4:m=numPop(ns);n=numPop(ns);numPush(ns,n/m);break;
}
}
charPop(cs);
i++;
break;
}
case 6:charPush(cs,s[i]);i++;break;
case 1:
{
while(IsChar(getcTop(cs))!=1&&IsChar(getcTop(cs))!=5&&IsChar(getcTop(cs))!=6)
{
switch(IsChar(getcTop(cs)))
{
case 2:charPop(cs);m=numPop(ns);n=numPop(ns);numPush(ns,n-m);break;
case 3:charPop(cs);m=numPop(ns);n=numPop(ns);numPush(ns,n*m);break;
case 4:charPop(cs);m=numPop(ns);n=numPop(ns);numPush(ns,n/m);break;
}
}
charPush(cs,s[i]);
i++;
break;
}
case 2:
{
while(IsChar(getcTop(cs))!=1&&IsChar(getcTop(cs))!=5&&IsChar(getcTop(cs))!=6)
{
switch(IsChar(getcTop(cs)))
{
case 2:charPop(cs);m=numPop(ns);n=numPop(ns);numPush(ns,n-m);break;
case 3:charPop(cs);m=numPop(ns);n=numPop(ns);numPush(ns,n*m);break;
case 4:charPop(cs);m=numPop(ns);n=numPop(ns);numPush(ns,n/m);break;
}
}
charPush(cs,s[i]);
i++;
break;
}
case 3:
{
while(IsChar(getcTop(cs))!=1&&IsChar(getcTop(cs))!=5&&IsChar(getcTop(cs))!=2&&IsChar(getcTop(cs))!=3&&IsChar(getcTop(cs))!=6)
{
charPop(cs);m=numPop(ns);n=numPop(ns);numPush(ns,n/m);break;
}
charPush(cs,s[i]);
i++;
break;
}
case 4:charPush(cs,s[i]);i++;break;
case 0:
{
int num=0;
while(IsChar(s[i])==0)
{
if(IsNum(s[i])==10)
{
if(s[i]!='\0')
{
cout<<"ÊäÈëÓÐÎó£¡"<<endl;
return false;
}
else
break;
}
else
{
m=IsNum(s[i]);
num=10*num+m;
i++;
}
}
// cout<<m<<endl;
numPush(ns,num);
break;
}
}
}
return true;
}
int calculate(numStack &ns,charStack &cs)
{
int m,n;
while(!iscEmpty(cs))
{
switch(IsChar(charPop(cs)))
{
case 1:m=numPop(ns);n=numPop(ns);numPush(ns,n+m);break;
case 2:m=numPop(ns);n=numPop(ns);numPush(ns,n-m);break;
case 3:m=numPop(ns);n=numPop(ns);numPush(ns,n*m);break;
case 4:m=numPop(ns);n=numPop(ns);numPush(ns,n/m);break;
case 6:cout<<"ÀšºÅ²»Æ¥Å䣡"<<endl;return 0;
}
}
return numPop(ns);
}
void main()
{
while(1)
{
char a[20];
cin>>a;
if(a[0]=='E')
return;
else {
numStack ns;
charStack cs;
InitnStack(ns);
InitcStack(cs);
if(translate(a,ns,cs)==true)
{
cout<<"------------------"<<endl;
cout<<a<<"="<<calculate(ns,cs)<<endl;
}
}
cout<<"ÊäÈëEÍ˳ö"<<endl;
cout<<endl;
}
}
2010-12-08 15:30
2010-12-08 16:01
2010-12-12 14:44
2010-12-12 15:29
