[HELP]C Programming , Stack conversion from infix to prefix
Code:
#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<ctype.h>
#define MAX 50
char output[MAX];
char stack[MAX];
char input[MAX];
char *s,*t;
char ch;
int top;
int l;
int opr;
void initialize(void);
void SetExpression(char*);
int PopFromStack(char);
int priority(char);
void ConvertToPrefix(void);
void ConvertToPostfix(void);
main (void)
{
initialize();
printf("\nEnter an expression in infix form:");
gets(input);
printf("\nSpecify output expression type,1)Prefix 2)Postfix");
ch=getch();
SetExpression(input);
if(ch=='1')
{
strrev(s);
ConvertToPrefix();
strrev(output);
printf("\nThe Prefix expression is:");
}
else
{
ConvertToPostfix();
printf("\nThe Postfix expression is:");
}
*(t)=opr;
t++;
opr=
PopFromStack();
}
PushOnStack((opr);
PushOnStack((*(s));
}
else PushOnStack(*(s));
s++;
}
if(*(s)=='(')
{
opr=PopFromStack();
while(opr!=')')
{
opr=PopFromStack();
}
s++;
}
}
while(top!=-1)
{
opr=PopFromStack();
*(t)=opr;
t++;
}
t++;
}
char opr;
while(*(s))
{
if(*(s))==''||*(s)=='\t')
{
s++;
continue;
}
if(isdigit(*(s))||isalpha(*(s)))
{
while(isdigit(*(s))||isalpha(*
(s)))
{
*(t)=*(s);
s++;
t++;
}
}
if(*(s)=='(')
{
PushOnStack(*(s));
s++;
}
if(*(s)=='*'||*(s)=='+'||*(s)
=='/'||*(s)=='%'||*(s)=='-'||*(s)
=='^')
{
if(top!=-1)
{
opr=PopFromStack();
while(priority(opr)>=
priority(*(s)))
{
*(t)=opr;
t++;
opr=
PopFromStack();
}
PushOnStack(opr);
PushOnStack(*(s));
}
else PushOnStack(*(s));
s++;
}
if(*(s)==')')
{
opr=PopFromStack();
while(opr!='(')
{
*(t)=opr;
t++;
opr=PopFromStack();
}
s++;
}
while(top!=-1)
{
opr=PopFromStack();
*(t)=opr();
t++;
}
t++;
}
getch();
}
Please help me , with some errors .
http://i44.tinypic.com/11cfx28.png
my output should look like this ..
Enter an expression in infix form: (9+6)/(2*4)^15
Specify output epression type,1) Prefix 2)Postfix
The Prefix expression is: /+96^*2415
----------------------------------------------
Enter an expression in infix form: (9+6)/(2*4)^15
Specify output epression type,1) Prefix 2)Postfix
The Postfix expression is:96+24*15^/
