归并排序是典型的采用分治法的算法，可以将一个无序序列变的有序，其步骤是将序列分成若干个有序序列，然后在将有序序列合并。

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		 int[] nums = { 4,23,22,7,1,8 };  
		 sort(nums, 0, nums.length-1);
		 System.out.println(Arrays.toString(nums));
	}
	
	
	 public static void merge(int[] nums, int low, int mid, int high) {  
	        int[] temp = new int[high - low + 1];  
	        int i = low;// 左指针  
	        int j = mid + 1;// 右指针  
	        int k = 0;  
	  
	        // 把较小的数先移到新数组中  
	        while (i <= mid && j <= high) {  
	            if (nums[i] < nums[j]) {  
	                temp[k++] = nums[i++];  
	            } else {  
	                temp[k++] = nums[j++];  
	            }  
	        }  
	  
	        // 把左边剩余的数移入数组  
	        while (i <= mid) {  
	            temp[k++] = nums[i++];  
	        }  
	  
	        // 把右边边剩余的数移入数组  
	        while (j <= high) {  
	            temp[k++] = nums[j++];  
	        }  
	  
	        // 把新数组中的数覆蓋nums数组  
	        for (int k2 = 0; k2 < temp.length; k2++) {  
	            nums[k2+low] = temp[k2];  
	        }  
	    }  
	    public static int[] sort(int[] nums, int low, int high) {  
	        int mid = (low + high) / 2;  
	        if (low < high) {  
	            // 左边  
	            sort(nums, low, mid);  
	            // 右边  
	            sort(nums, mid + 1, high);  
	            // 左右归并  
	            merge(nums, low, mid, high);  
	        }  
	        return nums;  
	    }