#include "bits/stdc++.h"

using namespace std;

const int mod = 998244353;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    string s;
    int d;
    cin >> s >> d;
    map<char, int> cnt;
    for (auto c : s) {
        cnt[c] = 1;
    }
    {
        char z = 'A';
        while (cnt.find(z) != cnt.end()) {
            z++;
        }
        for (char c = 'A'; c <= 'Z'; c++) {
            if (cnt.find(c) == cnt.end()) {
                cnt[z]++;
            }
        }
    }
    int n = (int) s.size(), ans = 0;
    map<vector<int>, int> dp, dp2;
    {
        vector<int> f(n + 1);
        iota(f.begin(), f.end(), 0);
        dp[f]++;
        if (f.back() == d) {
            ans++;
        }
    }
    for (int l = 1; l <= n + d; l++) {
        dp2.clear();
        for (auto& [c, y] : cnt){
            for (auto& [arr, x] : dp) {
                vector<int> f(n + 1, (int) 1e9);
                f[0] = l;
                for (int i = 1; i <= n; i++) {
                    f[i] = min(f[i], f[i - 1] + 1);
                    f[i] = min(f[i], arr[i] + 1);
                    f[i] = min(f[i], arr[i - 1] + (int) (s[i - 1] != c));
                }
                dp2[f] = (dp2[f] + x * 1ll * y % mod) % mod;
            }
        }
        dp = dp2;
        for (auto& [arr, x] : dp) {
            if (arr.back() == d) {
                ans = (ans + x) % mod;
            }
        }
    }
    cout << ans << '\n';
}