#include<stdio.h>

int card[10];
int flag[100000000] = {0};

int main(void)
{
  unsigned long int num, i;
  int j, k, l, m, n;
  char buf[255];

  scanf("%d %d", &n, &k);

  for(i = 0; i < n; i++)
    {
      scanf("%d", &card[i]);
    }

  if(k == 2)
    {
      for(i = 0; i < n; i++)
	{
	  for(j = 0; j < n; j++)
	    {
	      if(j == i) continue;
	      sprintf(buf, "%d%d", card[i], card[j]);
	      num = atol(buf);
	      flag[num] = 1;
	    }
	}
    }
  else if(k == 3)
    {
      for(i = 0; i < n; i++)
	{
	  for(j = 0; j < n; j++)
	    {
	      if(j == i) continue;
	      for(l = 0; l < n; l++)
		{
		  if(l == i || l == j) continue;
		  sprintf(buf, "%d%d%d", card[i], card[j], card[l]);
		  num = atol(buf);
		  flag[num] = 1;
		}
	    }
	}
    }
  else if(k == 4)
    {
      for(i = 0; i < n; i++)
	{
	  for(j = 0; j < n; j++)
	    {
	      if(j == i) continue;
	      for(l = 0; l < n; l++)
		{
		  if(l == i || l == j) continue;
		  for(m = 0; m < n; m++)
		    {
		      if(m == i || m == j || m == l) continue;
		      sprintf(buf, "%d%d%d%d", card[i], card[j], card[l], card[m]);
		      num = atol(buf);
		      flag[num] = 1;
		    }
		}
	    }
	}
    }


  unsigned long int count = 0;
  for(i = 0; i < 100000000; i++)
    {
      if(flag[i]) count++;
    }

  printf("%d\n", count);

  return 0;
}