var tfieldsize=36; //needs to be an even number
var numberofpairs=tfieldsize/2
var field_contains_piece = new Array(tfieldsize+5);
//the following variables arevreset in initgame()
var foundnumberofpairs=0; 
var first=0
var second=0
var moves=0
var UcantMove=true
for (n=1;n<(tfieldsize+1);n++)  field_contains_piece[n]=Math.floor(n/2+0.5)

function pic_is(imgname)

{
if (!(document.images)) return "non compatibile browser";

// eval("fn=window.document.playfield.p"+imgname+".src")
fn=document.images["p"+imgname].src

l=fn.length

filename=fn.substring(l-5,l)

return filename
}


function display_piece(piec)
{
eval("window.document.playfield.p"+piec+".src='"+field_contains_piece[piec]+".gif'")
}

function hide_piece(piec)
{
eval("window.document.playfield.p"+piec+".src='0.gif'")
}

function hide()
{
UcantMove=false
hide_piece(first)
hide_piece(second)
second=0
first=0
}

function clickon(field)
{
if (UcantMove) return;
if (!(pic_is(field)=="0.gif")) return;
display_piece(field)
if (first==0 || field==first)
 	{
	first=field;
	return;
	}
UcantMove=true
second=field
moves++
if(field_contains_piece[first]!=field_contains_piece[second]) 
	{
	setTimeout("hide()",1500)
	return;
	}

first=0
second=0
foundnumberofpairs++
if (foundnumberofpairs==numberofpairs) alert("Herzlichen Glückwunsch sie haben die paare in "+moves+". Versuchen gefunden !")
UcantMove=false
}

function randomise()
{
for (n=1;n<(tfieldsize+1);n++)
	{
	tmp=Math.floor(Math.random()*tfieldsize+1)
	swaptemp=field_contains_piece[tmp]
 	field_contains_piece[tmp]=field_contains_piece[n]
 	field_contains_piece[n]=swaptemp
	}

}


function initgame()
{
foundnumberofpairs=0; //reset in init
first=0
second=0
moves=0

for (n=1;n<(tfieldsize+1);n++)
	{
	field_contains_piece[n]=Math.floor(n/2+0.5);
	hide_piece(n);
	}
randomise()
UcantMove=false
}

        a = new Image(60, 60)
        a.src = "0.gif" 
        b = new Image(60, 60)
        b.src = "1.gif" 
        c = new Image(60, 60)
        c.src = "2.gif" 
        d = new Image(60, 60)
        d.src = "3.gif" 
        e = new Image(60, 60)
        e.src = "4.gif" 
        f = new Image(60, 60)
        f.src = "5.gif" 
        g = new Image(60, 60)
        g.src = "6.gif" 
        h = new Image(60, 60)
        h.src = "7.gif" 
        i = new Image(60, 60)
        i.src = "8.gif" 
        j = new Image(60, 60)
        j.src = "9.gif"
        k = new Image(60, 60)
        k.src = "10.gif" 
        l = new Image(60, 60)
        l.src = "11.gif" 
        m = new Image(60, 60)
        m.src = "12.gif" 
        n = new Image(60, 60)
        n.src = "13.gif" 
        o = new Image(60, 60)
        o.src = "14.gif" 
        p = new Image(60, 60)
        p.src = "15.gif" 
        q = new Image(60, 60)
        q.src = "16.gif" 
        r = new Image(60, 60)
        r.src = "17.gif" 
        s = new Image(60, 60)
        s.src = "18.gif"