char * dup(ParmString str) {return dup_top(str);}
/* reverse Polish calculator */
int main()
{
int type;
int print = 0;
int swaps = 0;
double op2;
unsigned int mod;
char s[MAXOP];
while ((type = getop(s)) != EOF) {
switch (type) {
case NUMBER:
push(atof(s));
break;
case '+':
push(pop() + pop());
break;
case '*':
push(pop() * pop());
break;
case '-':
op2 = pop();
push(pop() - op2);
break;
case '%':
op2 = pop();
if (op2 != 0.0)
push((unsigned int) pop() % (unsigned int) op2);
else
/* possibly clear the stack here, see 4-6 */
printf("error: no mod-zero\n");
break;
case '/':
op2 = pop();
if (op2 != 0.0)
push(pop() / op2);
else
/* possibly clear the stack here, see 4-6 */
printf("error: zero divisor\n");
break;
case 'p':
print = 1;
print_top();
break;
case 'd':
dup_top();
break;
case 'c':
clear_stack();
break;
case 's':
swaps = 1;
swap();
break;
case '\n':
if (print || swaps)
swaps = print^=print;
else
printf("\t%.8g\n", pop());
break;
default:
printf("error: unknown command %s\n", s);
break;
}
}
return 0;
}
