#include <stdio.h>
#include <ctype.h>
#include <string.h>
int stack[10];
int tos =-1;
void push(char x){
stack[++tos] = x;
}
int pop(){
return stack[tos--];
}
void main(){
char exp[10];char *e;
int num1, num2, num3, len;
printf("Enter Prefix expression>> ");
scanf("%s",exp);
len = strlen(exp);
e = &exp[len-1];
while(len!=-1){
if (isdigit(*e)) push(*e-48);
else{
num1 = pop();
num2 = pop();
switch(*e){
case '+': num3 = num1 + num2; break;
case '-': num3 = num1 - num2; break;
case '*': num3 = num1 * num2; break;
case '/': num3 = num1 / num2; break;
case '^': num3 = num1 ^ num2; break;
}
push(num3);
}
e--;len--;
}
printf("Value of the Expression >> %d\n",pop());
}