(Stack.size() > 0) { ResultArr.add(Stack.get(Stack.size()-1)); Stack.remove(Stack.size() - 1); } i=0; while (ResultArr.size()>1){ //Calculating postfix expression if (ResultArr.get(i).length()==1&&(ResultArr.get(i).charAt(0)=='+'||ResultArr.get(i).charAt(0)=='-...