Complete the following code, its supposed to take in an infix and convert it into its postfix equivalent and also solve it (If the infix expression is 2 + 3 * 6 - 1, then its postfix version is 2 3 6 * + 1 - ). The program must not ask for any kind of input from the user. No file reading is required too. You must assume the following regarding the input infix expressions: They will contain only integers as operands. The only operator they can contain are these four: *, /, +, - They will not contain any parenthesis or any kind of brace. A number and a operator are separated by a whitespace. Example: 2844 + 33 * 49 - 9 / 67.

public class InfixToPostfixConverter {

private static class Stack {

private E[] stackArray;

private int stackTop = -1;

@SuppressWarnings("unchecked")

Stack(int capacity) {

stackArray = (E[])new Object[capacity];

}

public int size() {

return (stackTop + 1);

}

public E top() {

if (isEmpty())

return null;

return stackArray[stackTop];

}

public boolean isEmpty() {

return (stackTop == -1);

}

public void push(E item) {

if (size() == stackArray.length)

throw new IllegalStateException("Stack is full");

stackArray[++stackTop] = item;

}

public E pop() {

if (isEmpty())

return null;

E answer = stackArray[stackTop];

stackArray[stackTop] = null;

stackTop--;

return answer;

}

public String toString() {

StringBuilder sb = new StringBuilder("[ ");

for (int pos = stackTop; pos >= 0; pos--) {

sb.append(stackArray[pos]);

if (pos > 0)

sb.append(" , ");

}

sb.append(" ]");

return sb.toString();

}

}

public static String infix2Postfix(String infixExpression) {

StringBuilder postfixExpression = new StringBuilder();

Stack operatorStack = new Stack<>(infixExpression.length());

operatorStack.push('*');

operatorStack.push('+');

operatorStack.push('/');

System.out.println(operatorStack);

/*System.out.println(operatorStack.pop());

System.out.println(operatorStack.pop());

System.out.println(operatorStack.pop());

System.out.println(operatorStack.pop());*/

// Implement the algorithm here

return postfixExpression.toString();

}

public static double postfixEvaluator(String postfixExpression) {

double expressionValue = 0;

Stack operandStack = new Stack<>(postfixExpression.length());

/*operandStack.push(10.0);

operandStack.push(20.0);

operandStack.push(30.0);

System.out.println(operandStack.pop());

System.out.println(operandStack.pop());

System.out.println(operandStack.pop());

System.out.println(operandStack.pop());*/

// Implement the algorithm here

return expressionValue;

}

public static void main(String[] args) {

System.out.println(InfixToPostfixConverter.infix2Postfix("29 + 378 / 998"));

//System.out.println(InfixToPostfixConverter.postfixEvaluator("2 3 +"));

//String postExpr = InfixToPostfixConverter.infix2Postfix("62 - 378 + 0 + 99");

//System.out.println(postExpr);

//System.out.println(InfixToPostfixConverter.postfixEvaluator(postExpr));

}

}