how to extract character from NSString ..XCode

Hi
Its really good being able to extract characters from NSstring as characters can be mathematically manipulated …here is the code snippet
    unichar c[2];
    char b;
    NSRange range={0,2};
    [@”a1″ getCharacters:c range:range];
    printf(“%c%c”,c[0],c[1]);
A pat on the back !!