中缀表达式转换为后缀表达式C语言程序.doc
文本预览下载声明
//1.h
#ifndef STACK_H
#define STACK_H
#includestdio.h
#includestdlib.h
typedef struct astack *Stack;
typedef struct astack
{
int top;
int maxtop;
char* data;
}Astack;
Stack NewEmpty(int size)
{
Stack S=(Stack)malloc(sizeof(Astack));
S-maxtop=size;
S-top=-1;
S-data=(char*)malloc(size*sizeof(char));
return S;
}
int StackEmpty(Stack S)
{
return S-top0;
}
int StackFull(Stack S)
{
return S-top==S-maxtop;
}
int Peek(Stack S)
{
return S-data[S-top];
}
void Push(char x,Stack S)
{
if(StackFull(S))
{
printf(Stack is full!\n);
exit(1);
}
else
S-data[++S-top]=x;
}
int Pop(Stack S)
{
if(StackEmpty(S))
{
printf(Stack is empty!\n);
exit(1);
}
else
return S-data[S-top--];
}
Stack NewStack(int size)
{
Stack S=NewEmpty(size);
int i,x,num;
printf(Please enter the number of data:\n);
scanf(%d,num);
for(i=0;inum;i++)
{
printf(Please enter the %d date:\n,i+1);
scanf(%c,x);
Push(x,S);
}
return S;
}
void ShowStack(Stack S)
{
int i;
for(i=0;i=S-top;i++)
{
printf( %c,S-data[i]);
}
printf(\n);
}
#endif
//1.c
#includestdio.h
#includestdlib.h
#includectype.h
#include1.h
#define MAX 30
int Precedence(char ch)
{
if(ch==+||ch==-)return 2;
else if(ch==*||ch==/)return 3;
else if(ch==(||ch==))return 4;
else if(ch==@)return 1;
else return 0;
}
void Change(char *s1,char *s2)
{
Stack S=NewEmpty(MAX);
int i=0,j=0,one=0;
char ch=s1[i];
Push(@,S);
while(ch!=@)
{
if(ch== )
ch=s1[++i];
else if(isalnum(ch)!=0)
{
if(one==1)
{
s2[j++]= ;
}
s2[j++]=ch;
ch=s1[++i];
one=0;
}
else if(ch==()
{
Push(ch,S);
ch=s1[++i];
one=1;
}
else if(ch==))
{
while(Peek(S)!=()
s2[j++]=Pop(S);
Pop(S);
ch=s1[++i];
one=1;
}
else if(ch==+||ch==-||ch==*||ch==/)
{
while(Peek(S)!=(Precedence(Peek(S))=Precedence(ch))
{
s2[j++]=Pop(S);
one=1;
}
Push(ch,S);
ch=s1[++i];
one=1;
}
}
while(StackEmpty(S)!=1)
{
s2[j++]=Pop(S);
one=1;
}
s2[j]=\0;
}
int main()
{
ch
显示全部