thamilvaanan

[CODE]this.getAppComboBox().getSelectedItem().toString();[/CODE] Is the one throws this exception. So check this.getAppComboBox() is null or not. Just comment [CODE]this.getAppComboBox().getSelectedItem().toString();[/CODE] and next to that add this and test it. [CODE]if(this.getAppComboBox()==null) { System.out.println("this.getAppComboBox() is returned a null value"); }[/CODE]

Please post you code with in code-tags. else hard to read. Only looking at the Exception we can guess that your trying to use an object which is null. >>>>java.lang.NullPointerException

Yes finding the proper algorithm is the key to solve this problem, I just tried with a straight forward algorithm(i.e to checck all possible sums in a proper sequence). This may not be the best but works fine. Sorry for not using comments. Here is the code. I also placed …