SOURCE

var a = [18,41,2,31,6,85,1,25,16];
console.log(a)
for (var i=0; i<a.length-1; i++) {
    for (var j=0; j<a.length-1-i; j++) {
        if (a[j] < a[j+1]) {
            var temp = a[j+1];
            a[j+1] = a[j];
            a[j] = temp;
        }
    }
}
console.log(a)