Need to search data for a last name, and THEN

i need to be able to adjust the following code. I have too many people w/last names ending in “S,” so i have to break it up into 2 groups: last names Sa - Sl, and last names Sm - Sz.

code follows:

if(lastname[x].substring(1,0) == “A” || lastname[x].substring(1,0) == “B” || lastname[x].substring(1,0) == “C” || lastname[x].substring(1,0) == “D” || lastname[x].substring(1,0) == “E” || lastname[x].substring(1,0) == “F” || lastname[x].substring(1,0) == “G” || lastname[x].substring(1,0) == “H” || lastname[x].substring(1,0) == “I” || lastname[x].substring(1,0) == “J” || lastname[x].substring(1,0) == “K” || lastname[x].substring(1,0) == “L”){
currentHALF = “1st”
}
else if(lastname[x].substring(1,0) == “M” || lastname[x].substring(1,0) == “N” || lastname[x].substring(1,0) == “O” || lastname[x].substring(1,0) == “P” || lastname[x].substring(1,0) == “Q” || lastname[x].substring(1,0) == “R” || lastname[x].substring(1,0) == “S” || lastname[x].substring(1,0) == “T” || lastname[x].substring(1,0) == “U” || lastname[x].substring(1,0) == “V” || lastname[x].substring(1,0) == “W” || lastname[x].substring(1,0) == “X” || lastname[x].substring(1,0) == “Y” || lastname[x].substring(1,0) == “Z”){
currentHALF = “2nd”
}

here’s what i currently have, but it’s not working:

else if(_root.currentdatatype == “lastname” && _root.currentdataID == “Sa” && lastname[x] == “S” + “a” && currentHALF == “1st”){
tempLASTNAMEnormalized = “Sa”
tempGRIDADDITION1 = “”
tempGRIDADDITION2 = " (Last Names Beginning With Sa)"
}

the data is accessed by selecting the options through a pulldown menu. any advice on how to do this would be much appreciated. i’m dealing with someone else’s code.