#include<bits/stdc++.h>
#include<string>

using namespace std;

#define ll long long int
#define ld long double
#define pb push_back
#define all(v) v.begin(),v.end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
#define deb(x) cout<< #x << '=' << x <<endl
#define MOD 1000000007

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    ll n , k;
    cin>>n>>k;
    ll a[n];
    map<ll , ll> mp;
    for(int i = 0; i < n; i++){
        cin>>a[i];
        mp[a[i]]++;
    }   
    ll ans = 0 , cur = 0;
    for(ll i = 0; i <= n; i++){
        ans += ((k - min(k , mp[i]))*i);
        k -= (k - min(k , mp[i]));
    }
    for(ll i = 0; i <= n; i++){
        if(mp[i] == 0){
            cur = i;
            break;
        }
    }
    ans += (k * (cur));
    cout<<ans;
    return 0;
}
#define _DEBUG
#include "bits/stdc++.h"
#define CHOOSE(a) CHOOSE2 a
#define CHOOSE2(a0,a1,a2,a3,a4,x,...) x
#define debug_1(x1) cout<<#x1<<": "<<x1<<endl
#define debug_2(x1,x2) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<endl
#define debug_3(x1,x2,x3) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<endl
#define debug_4(x1,x2,x3,x4) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<", "#x4<<": "<<x4<<endl
#define debug_5(x1,x2,x3,x4,x5) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<", "#x4<<": "<<x4<<", "#x5<<": "<<x5<<endl
#ifdef _DEBUG
#define debug(...) CHOOSE((__VA_ARGS__,debug_5,debug_4,debug_3,debug_2,debug_1,~))(__VA_ARGS__)
#else
#define debug(...)
#endif
#define rep(index,num) for(int index=0;index<(int)num;index++)
#define rep1(index,num) for(int index=1;index<=(int)num;index++)
#define brep(index,num) for(int index=(int)num-1;index>=0;index--)
#define brep1(index,num) for(int index=(int)num;index>0;index--)
#define scan(argument) cin>>argument
#define prin(argument) cout<<argument<<endl
#define kaigyo cout<<endl
#define eps 1e-7
#define mp(a1,a2) make_pair(a1,a2)
#define ALL(a) (a).begin(),(a).end()
#define rALL(a) (a).rbegin(),(a).rend()
#define puba(a) emplace_back((a))
typedef long long ll;
typedef long double ld;
using namespace std;
typedef pair<ll,ll> pll;
typedef pair<int,int> pint;
typedef vector<int> vint;
typedef vector<ll> vll;
typedef vector<pint> vpint;
typedef vector<pll> vpll;
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }
ll INFl=(ll)1e+18+1;
int INF=1e+9+1;
template<typename TypeInt>
std::string Itoa(const TypeInt v, int base)
{
    static const char table[] = "0123456789";
    string ret;
    static numeric_limits<TypeInt> t;
    TypeInt n = v;
    if (t.is_signed) {
        if (v < 0) n *= -1;
    }

    while (n >= base) {
        ret += table[n%base];
        n /= base;
    }
    ret += table[n];
    if (t.is_signed) {
        if (v < 0 && base == 10) ret += '-';
    }
    // 文字列の順番を逆にする
    std::reverse(ret.begin(), ret.end());

    return ret;
}
int main(){
	int N;
	scan(N);
	int ans=0;
	rep1(i,N){
		string s1=Itoa(i,10);
		string s2=Itoa(i,8);
		bool is=true;
		for(const auto& c:s1){
			if(c=='7'){
				is=false;
				break;
			}
		}
		for(const auto& c:s2){
			if(c=='7'){
				is=false;
				break;
			}
		}
		if(is) ans++;
	}
	prin(ans);
	return 0;
}
