static unsigned long get_result(const char *expr)
{
int position = 0;
unsigned long a, result = 0;
const char *expression;
nodelink *operator = NULL;
nodelink *operand = NULL;
expression = expr;
while (*(expression + position) != '\0'
&& *(expression + position) != '\n') {
switch (operator_class(*(expression + position))) {
case c_digit:
push(&operand, get_operand(expression + position, &position));
break;
case c_binop:
eval(&operator, &operand, *(expression + position));
push(&operator, *(expression + position));
break;
case c_rpar:
eval(&operator, &operand, ')');
if (operator->data == '(')
pop(&operator);
break;
case c_lpar:
push(&operator, '(');
break;
default:
printf("\nInvalid character in expression:");
a = 0;
while (*(expression + (int) a) != '\n'
&& *(expression + (int) a) != '\0') {
if (a != position)
printf("%c", *(expression + (int) a));
else
printf("<%c>", *(expression + (int) a));
a++;
}
return 0;
} /* end switch */
position++;
}
eval(&operator, &operand, ')');
result = pop(&operand);
DEBUGMSG(("expValueTable", "%s: %s -> %ld\n", __func__, expr, result));
return result;
}
unsigned long
get_result(char *expr)
{
int position = 0;
unsigned long op = 0, a = 0, b = 0, result = 0;
char *expression;
expression = expr;
while (*(expression + position) != '\0'
&& *(expression + position) != '\n') {
switch (operator_class(*(expression + position))) {
case 1:
push(&operand, get_operand(expression + position, &position));
break;
case 2:
if (operater != NULL)
while (operater != NULL
&& priority(*(expression + position)) <=
priority(operater->data)) {
a = pop(&operand);
b = pop(&operand);
op = pop(&operater);
push(&operand, calculate(op, b, a));
}
push(&operater, *(expression + position));
break;
case 3:
while (operater != NULL && operater->data != '(') {
a = pop(&operand);
b = pop(&operand);
op = pop(&operater);
push(&operand, calculate(op, b, a));
}
if (operater->data == '(')
pop(&operater);
break;
case 4:
push(&operater, '(');
break;
default:
printf("\nInvalid character in expression:");
a = 0;
while (*(expression + (int) a) != '\n'
&& *(expression + (int) a) != '\0') {
if (a != position)
printf("%c", *(expression + (int) a));
else
printf("<%c>", *(expression + (int) a));
a++;
}
exit(0);
} /* end switch */
position++;
}
while (operater != NULL) {
op = pop(&operater);
a = pop(&operand);
b = pop(&operand);
push(&operand, calculate(op, b, a));
}
result = pop(&operand);
return result;
}