JavaScript中九种常用排序算法

 function insertionSort(array) {
   if (Object.prototype.toString.call(array).slice(8, -1) === 'Array') {
     for (var i = 1; i < array.length; i++) {
       var key = array[i];
       var j = i - 1;
       while (j >= 0 && array[j] > key) {
         array[j + 1] = array[j];
         j--;
       }
      array[j + 1] = key;
    }
    return array;
  } else {
    return 'array is not an Array!';
  }
}

function binaryInsertionSort(array) {
   if (Object.prototype.toString.call(array).slice(8, -1) === 'Array') {
     for (var i = 1; i < array.length; i++) {
       var key = array[i], left = 0, right = i - 1;
       while (left <= right) {
         var middle = parseInt((left + right) / 2);
         if (key < array[middle]) {
           right = middle - 1;
         } else {
          left = middle + 1;
        }
      }
      for (var j = i - 1; j >= left; j--) {
        array[j + 1] = array[j];
      }
      array[left] = key;
    }
    return array;
  } else {
    return 'array is not an Array!';
  }
}

 function selectionSort(array) {
   if (Object.prototype.toString.call(array).slice(8, -1) === 'Array') {
     var len = array.length, temp;
     for (var i = 0; i < len - 1; i++) {
       var min = array[i];
       for (var j = i + 1; j < len; j++) {
         if (array[j] < min) {
           temp = min;
           min = array[j];
          array[j] = temp;
        }
      }
      array[i] = min;
    }
    return array;
  } else {
    return 'array is not an Array!';
  }
}

 function bubbleSort(array) {
   if (Object.prototype.toString.call(array).slice(8, -1) === 'Array') {
     var len = array.length, temp;
     for (var i = 0; i < len - 1; i++) {
       for (var j = len - 1; j >= i; j--) {
         if (array[j] < array[j - 1]) {
           temp = array[j];
           array[j] = array[j - 1];
           array[j - 1] = temp;
         }
       }
     }
     return array;
   } else {
     return 'array is not an Array!';
   }
 }

 //方法一
 function quickSort(array, left, right) {
   if (Object.prototype.toString.call(array).slice(8, -1) === 'Array' && typeof left === 'number' && typeof right === 'number') {
     if (left < right) {
       var x = array[right], i = left - 1, temp;
       for (var j = left; j <= right; j++) {
         if (array[j] <= x) {
           i++;
           temp = array[i];
           array[i] = array[j];
           array[j] = temp;
         }
       }
       quickSort(array, left, i - 1);
       quickSort(array, i + 1, right);
     };
   } else {
     return 'array is not an Array or left or right is not a number!';
   }
 } 
 var aaa = [3, 5, 2, 9, 1];
 quickSort(aaa, 0, aaa.length - 1);
 console.log(aaa);
 
 //方法二
 var quickSort = function(arr) {
 　　if (arr.length <= 1) { return arr; }
 　　var pivotIndex = Math.floor(arr.length / 2);
 　　var pivot = arr.splice(pivotIndex, 1)[0];
 　　var left = [];
 　　var right = [];
 　　for (var i = 0; i < arr.length; i++){
 　　　　if (arr[i] < pivot) {
 　　　　　　left.push(arr[i]);
 　　　　} else {
 　　　　　　right.push(arr[i]);
 　　　　}
 　　}
 　　return quickSort(left).concat([pivot], quickSort(right));
 };

 /*方法说明：堆排序
 @param array 待排序数组*/      
 function heapSort(array) {
   if (Object.prototype.toString.call(array).slice(8, -1) === 'Array') {
     //建堆
     var heapSize = array.length, temp;
     for (var i = Math.floor(heapSize / 2); i >= 0; i--) {
       heapify(array, i, heapSize);
     }
    
    //堆排序
    for (var j = heapSize - 1; j >= 1; j--) {
      temp = array[0];
      array[0] = array[j];
      array[j] = temp;
      heapify(array, 0, --heapSize);
    }
  } else {
    return 'array is not an Array!';
  }
}
/*方法说明：维护堆的性质
@param arr 数组
@param x  数组下标
@param len 堆大小*/
function heapify(arr, x, len) {
  if (Object.prototype.toString.call(arr).slice(8, -1) === 'Array' && typeof x === 'number') {
    var l = 2 * x, r = 2 * x + 1, largest = x, temp;
    if (l < len && arr[l] > arr[largest]) {
      largest = l;
    }
    if (r < len && arr[r] > arr[largest]) {
      largest = r;
    }
    if (largest != x) {
      temp = arr[x];
      arr[x] = arr[largest];
      arr[largest] = temp;
      heapify(arr, largest, len);
    }
  } else {
    return 'arr is not an Array or x is not a number!';
  }
}

 function mergeSort(array, p, r) {
   if (p < r) {
     var q = Math.floor((p + r) / 2);
     mergeSort(array, p, q);
     mergeSort(array, q + 1, r);
     merge(array, p, q, r);
   }
 }
 function merge(array, p, q, r) {
  var n1 = q - p + 1, n2 = r - q, left = [], right = [], m = n = 0;
  for (var i = 0; i < n1; i++) {
    left[i] = array[p + i];
  }
  for (var j = 0; j < n2; j++) {
    right[j] = array[q + 1 + j];
  }
  left[n1] = right[n2] = Number.MAX_VALUE;
  for (var k = p; k <= r; k++) {
    if (left[m] <= right[n]) {
      array[k] = left[m];
      m++;
    } else {
      array[k] = right[n];
      n++;
    }
  }
}

 /*方法说明：桶排序
 @param array 数组
 @param num  桶的数量*/
 function bucketSort(array, num) {
   if (array.length <= 1) {
     return array;
   }
   var len = array.length, buckets = [], result = [], min = max = array[0], regex = '/^[1-9]+[0-9]*$/', space, n = 0;
   num = num || ((num > 1 && regex.test(num)) "htmlcode">

 function countingSort(array) {
   var len = array.length, B = [], C = [], min = max = array[0];
   for (var i = 0; i < len; i++) {
     min = min <= array[i] ? min : array[i];
     max = max >= array[i] ? max : array[i];
     C[array[i]] = C[array[i]] ? C[array[i]] + 1 : 1;
   }
   for (var j = min; j < max; j++) {
     C[j + 1] = (C[j + 1] || 0) + (C[j] || 0);
   }
   for (var k = len - 1; k >=0; k--) {
     B[C[array[k]] - 1] = array[k];
     C[array[k]]--;
   }
   return B;
 }




3）算法分析
　　当输入的元素是n 个0到k之间的整数时，它的运行时间是 O(n + k)。计数排序不是比较排序，排序的速度快于任何比较排序算法。由于用来计数的数组C的长度取决于待排序数组中数据的范围（等于待排序数组的最大值与最小值的差加上1），这使得计数排序对于数据范围很大的数组，需要大量时间和内存。