日期:2014-05-16 浏览次数:20364 次
在pptv的实习结束了, 忙着找工作的事,顺便把数据结构的那本书重新复习了一遍。为了加深印象,特意把里面的常用的排序、查找算法用js写了一遍
具体的实例在我的github上,大家可以访问的: https://github.com/chenkehxx/practice js_sort.html文件
//js插入排序 function insertSort(arr){ var result =[]; result.push(arr[0]); for(var i = 1, len = arr.length; i < len; i++){ var el = arr[i]; if(result[i - 1] > el){ for(var j = 0; j < i; j++){ if(result[j] > el){ result.splice(j, 0, el); break; } } }else{ result.push(el); } } return result; }
//js的归并排序 function mergeSort(arr){ var len = arr.length; if(len > 1){ var index = Math.floor(len / 2); var left = arr.slice(0, index), right = arr.slice(index); return merge(mergeSort(left), mergeSort(right)); }else{ return arr; } function merge(left, right){ var arr = []; while(left.length && right.length){ if(left[0] < right[0]){ arr.push(left.shift()); }else{ arr.push(right.shift()); } } return arr.concat(left, right); } }
//js快排 function QuickSort(arr){ if(arr.length <= 1){ return arr; } var index = Math.floor(arr.length / 2); var key = arr.splice(index, 1)[0]; var left = [], right = []; for(var i = 0; i < arr.length; i++){ if(arr[i] < key){ left.push(arr[i]); }else{ right.push(arr[i]); } } return QuickSort(left).concat([key], QuickSort(right)); }
//js冒泡 function bubbleSort(arr){ var len = arr.length; for(var i = 0; i < len; i++){ for(var j = len -1; j > i; j--){ if(arr[j] > arr[j+1]){ var temp = arr[j]; arr[j] = arr[j+1]; arr[j + 1] = temp; } } } return arr;
//js二分查找 function binarySearch(arr, key, low, hight){ var mid = Math.floor((low + hight) / 2); var result = -1; console.log(key, low, hight, mid); if(key == arr[mid]){ result = mid; return result; }else if(key > arr[mid]){ hight = mid - 1; binarySearch(arr, key, low, hight); }else{ low = mid + 1; binarySearch(arr, key, low, hight); } return result; }常用的其他算法
//js查找两个数组中相同的元素 function findSame(arr1, arr2){ var len1 = arr1.length, len2 = arr2.length; var i = 0, j = 0, result = []; while(i < len1 && j < len2){ if(arr1[i] == arr2[j]) { result.push(arr1[i]); i++; j++; }else if(arr1[i] < arr2[j]){ i++; }else{ j++; } } return result; }
//js全排列 function sortAll(arr, flag){ var len = arr.length; if(len == flag){ console.log(arr); }else{ for(var i = flag; i < arr.length; i++){ swap(arr, i , flag); sortAll(arr, flag + 1);