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常用排序方法 —— JavaScript 實現

一、氣泡排序

	function bubbleSort(arr) {
	    var len = arr.length;
	    var temp;
	    for (var i = 0; i < len; i++) {
	        for (var j = 0; j < len - 1 - i; j++) {
	            if (arr[j] > arr[j+1]) {     
	                temp = arr[j+1];        
	                arr[j+1] = arr[j];
	                arr[
j] = temp; } } } return arr; }

二、選擇排序

	function selectionSort(arr) {
	    var len = arr.length;
	    var min, temp;
	    for (var i = 0; i < len - 1; i++) {
	        min = arr[i];
	        for (var j = i + 1; j < len; j++) {
	            if (arr[j] < min)
{ //尋找最小的數 min = arr[j]; //將最小數的索引儲存 } } temp = arr[i]; arr[i] = arr[minIndex]; arr[minIndex] = temp; } return arr; }

三、插入排序

	function insertionSort(arr) {
	    var len = arr.length;
	    var preIndex,
current; for (var i = 1; i < len; i++) { preIndex = i - 1; current = arr[i]; while(preIndex >= 0 && arr[preIndex] > current) { arr[preIndex+1] = arr[preIndex]; preIndex--; } arr[preIndex+1] = current; } return arr; }

四、快速排序

	function quickSort(arr, left, right) {
	    var len = arr.length,
	        partitionIndex;
	    if (left < right) {
	        partitionIndex = partition(arr, left, right);
	        quickSort(arr, left, partitionIndex-1);
	        quickSort(arr, partitionIndex+1, right);
	    }
	    return arr;
	}
	
	function partition(arr, left ,right) {     //分割槽操作
	    var pivot = left,                      //設定基準值(pivot)
	        index = pivot + 1;
	    for (var i = index; i <= right; i++) {
	        if (arr[i] < arr[pivot]) {
	            swap(arr, i, index);
	            index++;
	        }       
	    }
	    swap(arr, pivot, index - 1);
	    return index-1;
	}
	
	function swap(arr, i, j) {
	    var temp = arr[i];
	    arr[i] = arr[j];
	    arr[j] = temp;
	}