This calculator performs two digit task successfully but what do i need to alter it i want it to evaluate 3 digits
public class Calculator {
private long currentInput; //current input
private long previousInput; // previous input
private long result; // result of calculation
private String lastOperator = ""; // keeps track of the last operator entered
/* New digit entered as integer value i - moves currentInput 1 decimal place to the left and adds i in "one's column" */
public void inDigit(long i) {
currentInput = (currentInput * 10) + i;
}
/* Operator entered + - or * */
public void inOperator(String op) {
previousInput = currentInput; // save the new input as previous to get ready for next input
currentInput = 0;
lastOperator = op; // remember which operator was entered
}
/* Equals operation sets result to previousInput + - or * currentInput (depending on lastOperator) */
public void inEquals() {
if (lastOperator.equals("+")) {
result = previousInput + currentInput;
} else if (lastOperator.equals("-")) {
result = previousInput - currentInput;
} else if (lastOperator.equals("*")) {
result = previousInput * currentInput;
}
lastOperator = ""; // reset last operator to "nothing"
}
/* Clear operation */
public void inClear() {
currentInput = 0;
previousInput = 0;
result = 0;
lastOperator = "";
}
/* returns the current result */
public String getResult() {
return Long.toString(result); //converts int to String
}
/* returns the previous input value */
public String getPreviousInput() {
return Long.toString(previousInput);
}
/* returns the current input value */
public String getCurrentInput() {
return Long.toString(currentInput);
}
}