static void Main(string[] args)
        {
int[] arr = { 5,3,8,1,6,9,4};
int max;
int min;
            MaxMin(arr, out max,out min);
            Console.WriteLine("max={0},min={1}", max, min);
        }

static void MaxMin(int[] arr, out int max, out int min)
        {
            max = min = arr[0];
for (int i = 1; i < arr.Length; i++)
            {
if (arr[i] > max) max = arr[i];
if (arr[i] < min) min = arr[i];
            }
        }