function cachedGebid(id){
    var res = elementCache[id]
    if (res === void 0)
        res = elementCache[id] = document.getElementById(id)
    return res
}
var elementCache = {}


function show_one_hide_others(id_prefix,show_num,first,last) {
	for(i=first;i<=last;i++) {
		var elem = cachedGebid(id_prefix + i);
		if (elem != null) {
			if(i==show_num) {
				elem.style.display='block';
			} else {
				elem.style.display='none'
			}
		}
	}
}