function BubbleSort(element){
for(var i = 0;i<element.length;i++) {
for(var j = 0;j<element.length-1;j++){
if(element[j]>element[j+1]){
//把大的数字放到后面
var swap = element[j];
element[j] = element[j+1];
element[j+1] = swap;
}
}
}
return element
}
var element = [3,5,1,2,7,8,4,5,3,4];
console.log(BubbleSort(element))