#include <bits/stdc++.h>
#define FOR(i, a, n) for(ll i = (ll)a; i < (ll)n; i++)
#define FORR(i, n) for(ll i = (ll)n - 1LL; i >= 0LL; i--)
#define rep(i, n) FOR(i, 0, n)
#define ALL(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
template <typename T> using V = vector<T>;

constexpr int Mod = 998244353;
constexpr int mod = 1e9 + 7;
constexpr ll inf = 1LL << 60;

template <typename T> constexpr bool chmax(T &a, const T &b) {
    if(a >= b) return false;
    a = b;
    return true;
}
template <typename T> constexpr bool chmin(T &a, const T &b) {
    if(a <= b) return false;
    a = b;
    return true;
}

/*-------------------------------------------*/

template <int M> class ModInt {
    int x;

  public:
    constexpr ModInt() : x(0) {}
    constexpr ModInt(int64_t y) : x(y >= 0 ? y % M : (M - (-y) % M) % M) {}
    constexpr ModInt &operator+=(const ModInt &p) {
        if((x += p.x) >= M) x -= M;
        return *this;
    }
    constexpr ModInt &operator-=(const ModInt &p) {
        if((x += M - p.x) >= M) x -= M;
        return *this;
    }
    constexpr ModInt &operator*=(const ModInt &p) {
        x = (int)(1LL * x * p.x % M);
        return *this;
    }
    constexpr ModInt &operator/=(const ModInt &p) {
        *this *= p.inverse();
        return *this;
    }
    constexpr ModInt operator-() const { return ModInt(-x); }
    constexpr ModInt operator+(const ModInt &p) const {
        return ModInt(*this) += p;
    }
    constexpr ModInt operator-(const ModInt &p) const {
        return ModInt(*this) -= p;
    }
    constexpr ModInt operator*(const ModInt &p) const {
        return ModInt(*this) *= p;
    }
    constexpr ModInt operator/(const ModInt &p) const {
        return ModInt(*this) /= p;
    }
    constexpr bool operator==(const ModInt &p) const { return x == p.x; }
    constexpr bool operator!=(const ModInt &p) const { return x != p.x; }
    constexpr ModInt inverse() const {
        int a = x, b = M, u = 1, v = 0, t = 0;
        while(b > 0) {
            t = a / b;
            swap(a -= t * b, b);
            swap(u -= t * v, v);
        }
        return ModInt(u);
    }
    constexpr ModInt pow(const int64_t &n) const {
        ModInt ret(1), mul(x);
        int64_t k = n % (M - 1);
        if(k < 0) k += M - 1;
        while(k > 0) {
            if(k & 1) ret *= mul;
            mul *= mul;
            k >>= 1;
        }
        return ret;
    }
    constexpr friend ostream &operator<<(ostream &os, const ModInt &p) {
        return os << p.x;
    }
    constexpr friend istream &operator>>(istream &is, ModInt &a) {
        int64_t t = 0;
        is >> t;
        a = ModInt(t);
        return (is);
    }
};
using modint = ModInt<Mod>;

int main() {
    cin.tie(0);
    ios::sync_with_stdio(0);

    string s;
    cin >> s;
    int n = s.size();
    rep(i, n) {
        if(i == n - 1) {
            cout << 1 << endl;
            return 0;
        }
        if(s[i] != s[i + 1]) break;
    }
    if(n == 2) {
        cout << 2 << endl;
        return 0;
    }
    if(n == 3) {
        if(s[0] == s[1] || s[1] == s[2])
            cout << 6 << endl;
        else if(s[0] == s[2])
            cout << 7 << endl;
        else
            cout << 3 << endl;
        return 0;
    }
    int sum = 0;
    rep(i, n) sum += (int)(s[i] - 'a');
    modint dp[n + 1][2][3][4]; // idx, 連続したか, mod3, 直前の数
    dp[0][0][0][3] = 1;
    rep(i, n) rep(j, 3) rep(k, 4) rep(l, 3) {
        dp[i + 1][1][(j + l) % 3][l] += dp[i][1][j][k];
        dp[i + 1][k == l][(j + l) % 3][l] += dp[i][0][j][k];
    }
    modint ans;
    rep(i, 3) ans += dp[n][1][sum % 3][i];
    bool b = true;
    rep(i, n - 1) if(s[i] == s[i + 1]) b = false;
    if(b) ans += 1;
    cout << ans << endl;

    return 0;
}

Measured memory_bytes: 19348