排序算法

public class CountSort
    {
        public void Sort(ref int[] a)
        {
            int n=a.Length-1;
            int max = a[1];
            for (int i = 2; i <= n; i++)
            {
                if (a[i] > max) max = a[i];
            }
            int[] c = new int[max+1];
            for (int i = 1; i <= n; i++)
            {
                c[a[i]]++;
            }
            for (int i = 2; i <= max; i++)
            {
                c[i] = c[i] + c[i - 1];
            }
            int[] b = new int[n + 1];
            for (int i = 1; i <= n; i++)
            {
                b[c[a[i]]] = a[i];
                c[a[i]]--;
            }
            for (int i = 1; i <= n; i++)
            {
                a[i] = b[i];
            }
        }
    }

    public class BaseSort
    {
        int max=0;
        void MaxLength(int[] a)
        {
            for(int i=0;i<a.Length;i++)
            {
                int n=1;
                for (int j = 10; a[i] / j != 0; j *= 10)
                    n++;
                if (n > max) max = n;
            }      
        }

        int GetDit(int x,int i)
        {
            int n;
          
            n = x;
            for (int m = 1; m <= i; m++)
                n /= 10;
            n %= 10;

            return n;
        }
        public void Sort(ref int[] a)
        {
            ArrayList[] digit = new ArrayList[10];
            for (int i = 0; i <10; i++)
                digit[i] = new ArrayList();

            MaxLength(a);
            for (int i = 0; i < max; i++)
            {
                for(int j=0;j<a.Length;j++)
                {
                    int n;
                    n = GetDit(a[j],i);
                    digit[n].Add(a[j]);
                }
                int k=0;
                for (int t = 0; t < 10; t++)
                {
                    if (digit[t].Count == 0) continue;
                    foreach (object obj in digit[t])
                    {
                        a[k++] = (int)obj;
                    }
                }
                for (int j = 0; j < digit.Length; j++)
                    digit[j].Clear();
            }
 
        }
    }
}