#include<bits/stdc++.h>
using namespace std;
string s;
int n, ans, c;
char jl[10];
char x[20];
void dfs(int k)
{

    if(k == n)
    {
        int idx = 0;
        for(int i = 1; i <= n; i++)
        {
            for(int j = i; j <= n; j++)
            {
                if(jl[j] == s[j - i + 1])
                {
                    idx++;
                }
                else break;
            }
        }
        ans = max(ans, idx);
        return ;
    }
    for(int i = 1; i <= c; i++)
    {
        jl[k + 1] = x[i];
        dfs(k + 1);
    }
}
map<char, int>mp;
int main()
{
    freopen("string.in","r",stdin);
    freopen("string.out","w",stdout);
    ios::sync_with_stdio(0);
    cin.tie();
    cin >> s >> n;
    s = ' ' + s;
    for(int i = 1; i <= s.size(); i++)
    {
        if(!mp[s[i]])x[++c] = s[i];
        mp[s[i]] = 1;
    }

    if(n > 10)
    {
        cout << n;
        return 0;
    }
    dfs(0);
    cout << ans;
    return 0;
}