js基本算法:冒泡排序,二分查找的简单实例

function sort(elements){
 for(var i=0;ielements[j+1]){
  var swap=elements[j];
  elements[j]=elements[j+1];
  elements[j+1]=swap;
  }
 }
 }
}
 
var elements = [3, 1, 5, 7, 2, 4, 9, 6, 10, 8];
console.log('before: ' + elements);
sort(elements);
console.log(' after: ' + elements);

function quickSort(elements) {
 
　　if (elements.length <= 1) { return elements; }
 
  var pivotIndex = Math.floor(elements.length / 2);
 
  var pivot = elements.splice(pivotIndex, 1)[0];
 
 
　　var left = [];
 
　　var right = [];
 
　　for (var i = 0; i 

insertSort: function(elements) {

  var i = 1,
  j, step, key, len = elements.length;

  for (; i  -1) {
      if (elements[j] > key) {
        elements[j + 1] = elements[j];
      } else {
        break;
      }
    }

    elements[j + 1] = key;
  }

  return elements;
}

function binarySearch(data,item,start,end){
  var end=end || data.length-1;
  var start=start || 0;
  var m=Math.floor((start+end)/2);
  if(item==data[m]){
    return m;
  }else if(item

function binarySearch(data, item){
  var h = data.length - 1,
    l = 0;
  while(l <= h){
    var m = Math.floor((h + l) / 2);
    if(data[m] == item){
      return m;
    }
    if(item > data[m]){
      l = m + 1;
    }else{
      h = m - 1;
    }
  }
 
  return false;
}
var arr=[34,12,5,123,2,745,32,4];
binarySearch(arr,5);