function switchDIV(divid){
	
	var divstyle = document.getElementById(divid).style; //declare the div style into variable
    for(i = 1; i <= 46; i++){	
    	var divnum = 'div' + String(i);
    	var thisdiv = document.getElementById(divnum).style;
    	if(divid == divnum){
      		thisdiv.display = thisdiv.display? "":"block";
    	} else {
    		thisdiv.display = thisdiv.display? "":""; //change display style between default value and "block" (visible);
    	}
    }
}