PHP Decode

<?  var _0xc2f4 = ["length", 
    " ", 
    "challenge.jpg", 
    "5008_9c00_420.gif", 
    "getSeconds", 
    "floor", 
    "<imgsrc='", 
    "'>", 
    "write", 
    "BRTky.jpg", 
    "231ced7347e593276b", 
    "-", 
    "51e342ff63d20c", 
    "20201/", 
    "img", 
    "createElement", 
    "src", 
    "appendChild", 
    "body", 
    "href", 
    "location", 
    "<img src='" 
]; 
var warray = [_0xc2f4[0], 
    _0xc2f4[1], 
    _0xc2f4[2], 
    _0xc2f4[3], 
    _0xc2f4[4], 
    _0xc2f4[5], 
    _0xc2f4[6], 
    _0xc2f4[7], 
    _0xc2f4[8], 
    _0xc2f4[9], 
    _0xc2f4[10], 
    _0xc2f4[11], 
    _0xc2f4[12], 
    _0xc2f4[13] 
]; 
var sillydate = 0; 
var sillyvar = 0; 
 
function StringArray(_0x7efdx5) { 
    this[_0xc2f4[0]] = _0x7efdx5; 
    for (var _0x7efdx6 = 1; _0x7efdx6 <= _0x7efdx5; _0x7efdx6++) { 
        this[_0x7efdx6] = _0xc2f4[1] 
    } 
} 
image = new StringArray(10); 
image[0] = _0xc2f4[2]; 
image[1] = _0xc2f4[9]; 
image[2] = _0xc2f4[3]; 
image[3] = _0xc2f4[9]; 
image[4] = _0xc2f4[2]; 
image[5] = _0xc2f4[9]; 
image[6] = _0xc2f4[3]; 
image[7] = _0xc2f4[2]; 
image[8] = _0xc2f4[3]; 
image[9] = _0xc2f4[2]; 
var ran = 60 / image[_0xc2f4[0]]; 
 
function dateFn() { 
    sillydate = new Date(); 
    sillyvar = sillydate[_0xc2f4[4]](); 
    sillyvar = Math[_0xc2f4[5]](sillyvar / ran); 
    return (image[sillyvar]) 
} 
 
function boombay(_0x7efdxa) { 
    var _0x7efdxb = document[_0xc2f4[15]](_0xc2f4[14]); 
    _0x7efdxb[_0xc2f4[16]] = _0x7efdxa; 
    document[_0xc2f4[18]][_0xc2f4[17]](_0x7efdxb); 
    window[_0xc2f4[20]][_0xc2f4[19]] = _0x7efdxa 
} 
document[_0xc2f4[8]](_0xc2f4[21] + dateFn() + _0xc2f4[7]); 
//boombay(warray[12]+ warray[10]+ warray[11]+ warray[13]+"/") 
document.write("<img src='" + dateFn() + "'>"); ?>