#define _CRT_SECURE_NO_WARNINGS
#define _SILENCE_CXX17_C_HEADER_DEPRECATION_WARNING
#include <bits/stdc++.h>
using namespace std;
const int N = 5000050;
char s[N];
deque<int> pos[26];
int main()
{
    const auto sz = acos(-1);
    int k;
    scanf("%s%d", s, &k);
    int n = strlen(s);
    for (int i = 0; i < n; i++) pos[s[i] - 'a'].push_back(i);
    int lmost = 0, lsec = 0;
    while (pos[lmost].empty()) lmost++;
    lsec = lmost + 1;
    while (lsec < 26 && pos[lsec].empty()) lsec++;
	for (int i = 0; i < n; i++)
    {
        while (pos[lmost].size() && pos[lmost].front() < i) pos[lmost].pop_front();
        if (pos[lmost].empty())
        {
            while (pos[lmost].empty()) lmost++;
            lsec = lmost + 1;
            while (lsec < 26 && pos[lsec].empty()) lsec++;
        }
    }
    return 0;
}