자바 입문자입니다 후위표기식의 연산값이 원하는대로 안나오네요 도와주세요 ㅠㅠ
제가원하는값은 6인데 -48이 나옵니다 ㅠㅠ
class Node{
Object data; Node link;
Node(Object data){
this.data = data;
this.link = null;
}
}
class LinkedStack{
Node top;
LinkedStack(){
this.top = null;
}
boolean isEmpty() {
return top==null;
}
void push(Object data) {
Node newNode = new Node(data);
newNode.link = top;
top = newNode;
}
Object pop() {
if(isEmpty()) {
System.out.println("no data");
return 0;
}else {
Node temp = top;
top = temp.link;
return temp.data;
}
}
void delete() {
if(isEmpty()) {
System.out.println("no data");
}else {
top = top.link;
}
}
Object peek() {
if(isEmpty()) {
System.out.println("no data");
return 0;
}else {
return top.data;
}
}
void printStack() {
if(isEmpty()) {
System.out.println("no data");
}else {
Node temp = top;
while(temp != null) {
System.out.print(temp.data + " ");
temp = temp.link;
}
System.out.println();
}
}
}
class Operate{
public static char[] toPostfix(String infix) {
char testCh;
int stackSize = infix.length();
char[] postfix = new char[stackSize];
int j=0;
LinkedStack s = new LinkedStack();
for(int i=0; i<stackSize; i++) {
testCh = infix.charAt(i);
switch(testCh) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
postfix[j] = testCh;
j++;
break;
case '+':
case '-':
case '*':
case '/':
s.push(testCh);
break;
case ')':
postfix[j] = (char)s.pop();
j++;
break;
default:
}
}
postfix[j] = (char)s.pop();
return postfix;
}
public static int calPostfix(char[] postfix) {
int opr1;
int opr2;
int result=0;
LinkedStack s = new LinkedStack();
for(int i=0; i<postfix.length; i++) {
if(postfix[i]!='+' && postfix[i]!='-' && postfix[i]!='*' && postfix[i]!='/') {
s.push(postfix[i]-'0');
}else {
if(postfix[i]=='+') {
opr2 = (int)s.pop();
opr1 = (int)s.pop();
s.push(opr1+opr2);
}else if(postfix[i]=='-') {
opr2 = (int)s.pop();
opr1 = (int)s.pop();
s.push(opr1-opr2);
}else if(postfix[i]=='*') {
opr2 = (int)s.pop();
opr1 = (int)s.pop();
s.push(opr1*opr2);
}else {
opr2 = (int)s.pop();
opr1 = (int)s.pop();
s.push(opr1/opr2);
}
}
}
result = (int)s.pop();
return result;
}
}
public class HomeWork_01{
public static void main(String[] args) {
String infix = "(3*5)-((6/2)+(3*2))";
System.out.println(infix);
char[] postfix = Operate.toPostfix(infix);
System.out.println(postfix);
int result = Operate.calPostfix(postfix);
System.out.println(result);
}
}