public void sort(int[] arr, int b, int e){
		if(b>=e)return;
		int i = b, j = e, m = arr[(b+e)/2];
		do{
			while(arr[i] < m)i++;
			while(arr[j] > m)j--;
			if(i<=j){
				int tmp = arr[i];
				arr[i++] = arr[j];
				arr[j--] = tmp;
			}
		}
		while(i<=j);
		if(i<e) sort(arr, i, e);
		if(j>b) sort(arr, b, j);
		
	}