If you want to check everyone, you can modify this code that I use in my frequent fragger program
Code:
adm_check_slots(){
new maxslots = get_maxplayers()
new kickme = 0, playtime, unlimited = 0x7fffffff, adm_check_time
for(new i = 1; i <= maxslots; ++i){
if (!is_user_connected(i) && !is_user_connecting(i)) continue
if (get_user_flags(i) & ADMIN_RESERVATION) continue
playtime = get_user_time(i)
adm_check_time = (playtime + connecttime[i])
if(unlimited > adm_check_time){
unlimited = adm_check_time
kickme = i
}
}
return kickme
}