#include #include #include using std::cin; using std::cout; const char endl = '\n'; const int N = 5e5 + 5; const int mod = 114514; int n, sum[N][26], pre[26][26], suf[26][26], cnt[26]; long long ans; std::string s; int main() { std::ios::sync_with_stdio(false); cin.tie(nullptr); cin >> s; n = s.size(); s = ' ' + s; for (int i = 1; i <= n; i++) { std::copy_n(sum[i - 1], 26, sum[i]); sum[i][s[i] - 'a']++; } for (int i = n; i; i--) { cnt[s[i] - 'a']++; for (int j = 0; j < 26; j++) { if (s[i] - 'a' == j) continue; suf[s[i] - 'a'][j] = (suf[s[i] - 'a'][j] + cnt[j]) % mod; } } std::fill_n(cnt, 26, 0); for (int i = 1; i <= n; i++) { cnt[s[i] - 'a']++; for (int j = 0; j < 26; j++) { if (cnt[j] < 2 || s[i] - 'a' == j) continue; pre[s[i] - 'a'][j] = (pre[s[i] - 'a'][j] + (static_cast(cnt[j]) * (cnt[j] - 1) / 2) % mod) % mod; } for (int j = 0; j < 26; j++) { if (s[i] - 'a' == j) continue; suf[s[i] - 'a'][j] = (suf[s[i] - 'a'][j] - (sum[n][j] - sum[i - 1][j]) % mod + mod) % mod; } for (int j = 0; j < 26; j++) { for (int k = 0; k < 26; k++) { if (j == k || j == s[i] - 'a' || k == s[i] - 'a') continue; ans += static_cast(pre[k][j]) * suf[j][k]; } } ans %= mod; } cout << ans << endl; return 0; }