public String getValue(String input) {
infixString = input;
char[] cpostfix = new char[10];
int index = 0;
System.out.println("Infix exp : " + infixString);
MyStack s = new MyStack();
for (char c : infixString.toCharArray()) {
if (Character.isLetterOrDigit(c)) {
cpostfix[index] = c;
index++;
} else {
if (s.isEmpty()) s.push(c);
else {
if (pre(c) <= pre(s.peek())) {
while (!(s.isEmpty()) && (pre(c) <= pre(s.peek()))) {
if (!s.isEmpty()) {
char a = s.pop();
cpostfix[index] = a;
index++;
// System.out.println(cpostfix);
}
}
s.push(c);
} else {
s.push(c);
}
}
}
}
while (!s.isEmpty()) {
char a = s.pop();
cpostfix[index] = a;
index++;
}
System.out.print("Postfix exp: ");
System.out.println(cpostfix);
return new String(cpostfix);
}