Go: ///
// File:  0546.go
// Author: ymiyamoto
//
// Created on Tue Mar  6 23:19:41 2018
//
package main

import (
	"fmt"
)

var n, k int

func perm(arr []int) [][]int {
	if len(arr) == 1 {
		return [][]int{arr}
	}

	p := perm(arr[1:])
	var ret [][]int
	for _, val := range p {
		for i := 0; i <= len(val); i++ {
			tmp := make([]int, len(val))
			copy(tmp, val)
			tmp = append(tmp, 0)
			copy(tmp[i+1:], tmp[i:])
			tmp[i] = arr[0]
			ret = append(ret, tmp)
		}
	}

	return ret
}

func permutation(n, k int) [][]int {
	ret := [][]int{}

	for i := 0; i < 1<<uint(n); i++ {
		var selects []int
		for j := 0; j < n; j++ {
			if (i>>uint(j))&1 == 1 {
				selects = append(selects, j)
			}
		}
		if len(selects) == k {
			ret = append(ret, perm(selects)...)
		}
	}

	return ret
}

func main() {
	for {
		fmt.Scan(&n, &k)
		if n == 0 && k == 0 {
			break
		}

		cards := make([]string, n)
		for i := 0; i < n; i++ {
			fmt.Scan(&cards[i])
		}

		ret := permutation(len(cards), k)
		nums := map[string]bool{}
		for _, val := range ret {
			var num string
			for i := 0; i < len(val); i++ {
				num += cards[val[i]]
			}
			nums[num] = true
		}

		fmt.Println(len(nums))
	}
}

C++: #include <iostream>
#include <fstream>
#include <sstream>
#include <iomanip>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <deque>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <bitset>
#include <functional>
#include <utility>
#include <algorithm>
#include <numeric>
#include <typeinfo>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
#include <ctime>

using namespace std;

#define dump(n) cout<<"# "<<#n<<"="<<(n)<<endl
#define debug(n) cout<<__FILE__<<","<<__LINE__<<": #"<<#n<<"="<<(n)<<endl
#define repi(i,a,b) for(int i=int(a);i<int(b);i++)
#define rep(i,n) repi(i,0,n)
#define iter(c) __typeof((c).begin())
#define foreach(i,c) for(iter(c) i=(c).begin();i!=(c).end();i++)
#define allof(c) (c).begin(),(c).end()
#define mp make_pair

typedef unsigned int uint;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
typedef pair<int,int> pii;

string to_string(int n)
{
	char buf[10];
	sprintf(buf,"%d",n);
	return buf;
}

int main()
{
	for(int n,k;cin>>n>>k,n|k;){
		vi a(n);
		rep(i,n)
			cin>>a[i];
		
		vi p(n);
		rep(i,n)
			p[i]=i;
		
		set<string> s;
		do{
			string temp;
			rep(i,k)
				temp+=to_string(a[p[i]]);
			s.insert(temp);
			reverse(k+allof(p));
		}while(next_permutation(allof(p)));
		
		cout<<s.size()<<endl;
	}
	
	return 0;
}

C++: #include <cstdio>
#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <set>

using namespace std;

int n;
int k;

vector<int> card;
set< string > cd;

string VectorToString(vector<int>::iterator begin, vector<int>::iterator end){
	string str = "";
	char ch[256];
	for(;begin < end;begin++){
		sprintf(ch,"%d",*begin);
		str += ch;
	}
	return str;
}

string VectorToDebugText(const vector<int> &vec){
	string str = "";
	for(int i=0;i<vec.size();i++){
		char ch[256];
		sprintf(ch,"%d",vec[i]);
		str += ch;
		str += ":";
	}
	return str;
}


int main(){
	while(1){
		int self;
		scanf("%d %d",&n,&k);
		if(n == 0 && k == 0){
			break;
		}
		card.clear();
		cd.clear();
		for(int i=0;i<n;i++){
			scanf("%d",&self);
			card.push_back(self);
		}
		vector<int> cc(k);
	
		sort(card.begin(),card.end());
	
		while(next_permutation(card.begin(),card.end())){
			 cd.insert(VectorToString(card.begin(),card.begin()+k));
		}
		printf("%d\n",cd.size());
	}
}

C++: #include "bits/stdc++.h"

#define rep(i, n) for(int i = 0; i < (int)n; i++)
#define all(co) co.begin(), co.end()
using namespace std;
//using P = pair<int, int>;

int main() {
	int n;
	while (cin >> n && n) {
		int k; cin >> k;
		vector<string> vec(n);
		rep(i, n) cin >> vec[i];

		set<string> sets;
		vector<bool> used(n);
		void dfs(string str, int count) {
			if (count == k) {
				sets.insert(str);
				return;
			}
			rep(i, n) if (!used[i]) {
				used[i] = true;
				dfs(str + vec[i], count + 1);
				used[i] = false;
			}
		};
		dfs("", 0);
		cout << sets.size() << endl;
	}
	return 0;
}

C++: /* {{{ Shinobu kawaii */
/*
  ______   __        _                  __                 
.' ____ \ [  |      (_)                [  |                
| (___ \_| | |--.   __   _ .--.   .--.  | |.--.   __   _   
 _.____`.  | .-. | [  | [ `.-. |/ .'`\ \| '/'`\ \[  | | |  
| \____) | | | | |  | |  | | | || \__. ||  \__/ | | \_/ |, 
 \______.'[___]|__][___][___||__]'.__.'[__;.__.'  '.__.'_/ 

*/
/* }}} */

#include <bits/stdc++.h>
using namespace std;

// #define int long long
struct Fast {Fast(){std::cin.tie(0);ios::sync_with_stdio(false);}} fast;

/* cpp template {{{ */

/* short */
#define pb push_back
#define mp make_pair
#define Fi first
#define Se second
#define ALL(v) (v).begin(), (v).end()
#define X real()
#define Y imag()

/* REPmacro */
#define REPS(i, a, n) for (int i = (a); i < (n); ++i)
#define REP(i, n) REPS(i, 0, n)
#define RREP(i, n) REPS(i, 1, n + 1)
#define DEPS(i, a, n) for (int i = (a); i >= n; --i)
#define DEP(i, n) DEPS(i, n, 0)

/* debug */
#define debug(x) cerr << x << " " << "(L:" << __LINE__ << ")" << '\n';

/* typedef */
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef vector<vii> viii;
typedef pair<int, int> pii;
typedef double D;
typedef complex<D> P;

/* const */
const int INF = 999999999;
const int MOD = 1e9 + 7;
const D EPS = 1e-9;
const int dx[] = {0, 1, 0, -1, 1, -1, 1, -1}, dy[] = {1, 0, -1, 0, 1, -1, -1, 1};

/* func */
inline bool inside(int y, int x, int H, int W) {return y >= 0 && x >= 0 && y < H && x < W;}
inline int in() {int x; std::cin >> x; return x;}
template <typename T> void print(T x) {std::cout << x << '\n';}
template <typename T>
void print(std::vector<T>& v, string s = " ") {
  REP(i, v.size()) {
    if (i != 0) std::cout << s;
    std::cout << v[i];
  }
  std::cout << '\n';
}

/* }}} */

static int n, k;
vector<string> card;
unordered_set<string> chie;

signed main()
{
  while (cin >> n >> k, n || k) {
    card = vector<string>(n);
    REP(i, n) cin >> card[i];
    sort(ALL(card));
    do {
      string s;
      REP(i, k) s += card[i];
      chie.insert(s);
    } while (next_permutation(ALL(card)));
    print(chie.size());
    //cout << chie.size() << endl;
    chie.clear();
  }
  
  return 0;
}