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5. Postfix Eval.cpp
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5. Postfix Eval.cpp
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#include <stdio.h>
#include <conio.h>
#include <string.h>
#include <ctype.h>
#include <process.h>
int stack[20];
int top;
void push(int);
int pop();
void eval(char post[20]);
void main()
{
char post[20];
top=-1;
printf("Enter Postfix Expression : ");
gets(post);
eval(post);
printf("The Evaluated Anwer Is : %d",pop());
getch();
}
void push(int ele)
{
stack[++top]=ele;
}
int pop()
{
return (stack[top--]);
}
void eval(char post[20])
{
char ch;
int i,b,a;
for(i=0;post[i];i++)
{
ch=post[i];
if(isdigit(ch))
push(ch-'0');
else
{
b=pop();
a=pop();
switch(ch)
{
case '+':push(a+b);
break;
case '-':push(a-b);
break;
case '*':push(a*b);
break;
case '/':if(b==0)
{
printf("Devide By Zero");
getch();
exit(0);
}
push(a/b);
default:printf("Invalid Operation");
}
}
}
}
/*
License
=======
Copyright (C) 2011 SkyKOG
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/