JavaScript数组排序算法与sort方法详解

bubbleSort:function(array){
var i = 0, len = array.length, j, d; for(; i<len; i++){ 
for(j=0; j<len; j++){ 
if(array[i] < array[j]){ 
d = array[j]; array[j] = array[i]; array[i] = d; 
} 
} 
}
return array;
}

systemSort:function(array)
{ return array.sort(function(a, b)
{ return a - b; }); 
}

quickSort:function(array)
{ //var array = [8,4,6,2,7,9,3,5,74,5]; //var array = [0,1,2,44,4,324,5,65,6,6,34,4,5,6,2,43,5,6,62,43,5,1,4,51,56,76,7,7,2,1,45,4,6,7]; 
var i = 0; var j = array.length - 1; var Sort = function(i, j){ 
// 结束条件 
if(i == j ){ return }; var key = array[i]; var tempi = i;
// 记录开始位置 var tempj = j; // 记录结束位置 
while(j > i){ 
// j <<-------------- 向前查找 
if(array[j] >= key){ j--; }
else{ 
array[i] = array[j] //i++ ------------>>向后查找 
while(j > ++i){ if(array[i] > key){ 
array[j] = array[i]; break; 
} 
} 
} 
} // 如果第一个取出的 key 是最小的数 
if(tempi == i){ 
Sort(++i, tempj); return ; 
} 
// 最后一个空位留给 
key array[i] = key; 
// 递归 Sort(tempi, i); 
Sort(j, tempj); } Sort(i, j); 
return array; 
}

//Jun.array.shellSort(Jun.array.df(10000)); 
shellSort:function(array){
// var array = [13,14,94,33,82,25,59,94,65,23,45,27,73,25,39,10]; 
var tempArr = [1750, 701, 301, 132, 57, 23, 10, 4, 1]; 
// reverse() 在维基上看到这个最优的步长 较小数组 
//var tempArr = [1031612713, 217378076, 45806244, 9651787, 2034035, 428481, 90358, 19001, 4025, 836, 182, 34, 9, 1] 
//针对大数组的步长选择 
var i = 0; var tempArrtempArrLength = tempArr.length; var len = array.length; var len2 = parseInt(len/2); for(;i < tempArrLength; i++){ 
if(tempArr[i] > len2){ continue; } tempSort(tempArr[i]); 
} 
// 排序一个步长 
function tempSort(temp){
//console.log(temp) 使用的步长统计 
var i = 0, j = 0, f, tem, key; 
var tempLen = len%temp > 0 ? parseInt(len/temp) + 1 : len/temp; 
for(;i < temp; i++){
// 依次循环列 
for(j=1;/*j < tempLen && */temp * j + i < len; j++){ 
//依次循环每列的每行 
tem = f = temp * j + i; key = array[f]; 
while((tem-=temp) >= 0){ 
// 依次向上查找 
if(array[tem] > key){
array[tem+temp] = array[tem]; 
}else{ break; 
} 
} array[tem + temp ] = key; 
} 
} 
} return array;
}

insertSort:function(array){
/ /var array = [0,1,2,44,4,324,5,65,6,6,34,4,5,6,2,43,5,6,62,43,5,1,4,51,56,76,7,7,2,1,45,4,6,7]; 
var i = 1, j, temp, key, len = array.length; 
for(; i < len; i++){ 
temp = j = i; key = array[j]; while(--j > -1){ 
if(array[j] > key){ array[j+1] = array[j]; }else{ break; 
} 
}
array[j+1] = key; 
} return array; 
}

var arrDemo = new Array();
arrDemo[0] = 10;
arrDemo[1] = 50;
arrDemo[2] = 51;
arrDemo[3] = 100;
arrDemo.sort(); //调用sort方法后，数组本身会被改变，即影响原数组
alert(arrDemo);//10,100,50,51 默认情况下sort方法是按ascii字母顺序排序的，而非我们认为是按数字大小排序
arrDemo.sort(function(a,b){return a>b?1:-1});//从小到大排序
alert(arrDemo);//10,50,51,100
arrDemo.sort(function(a,b){return a<b?1:-1});//从大到小排序
alert(arrDemo);//100,51,50,10