Search Key By Key

I'm not a web developer (I write in DELPHI and C++), but I was asked to help with the little problem which is based on javascript (never touched before now).A problem is to write a search engine in JavaScript only (The "application" works only on HTML and JS files). For easier explanation I'll change a topic of the problem and instead I'll talk about countries.There is a map of the world. All the countries are included in the JS file which looks like this (it's only a little piece):[code]And now I have a list (jpg files) and when I touch the flag or country's name It's highlighted on the map. Now I want to create a search engine which works in the way that instead of country names I have an alphabet button and the textbox. If I press a letter "N", I want to list (in [for example] the LISTBOX item) all the countries which the first letter is "N". Then if I press "I" I want to refresh the list and get all the coutries which begins with "NI", and so on. After this I'll do links which permits to click on the search result and show the listed countries on the map.I can't do this, and unfortunately can't tell that I don't know HOW, bcause I promissed to do this in 3 days, but it's too hard for me to do this in JS.