#include <bits/stdc++.h>

using namespace std;

const int mod = 998244353;
int add(int x, int y) {
    x += y;
    if(x >= mod) x -= mod;
    return x;
}
int sub(int x, int y) {
    x -= y;
    if(x < 0) x += mod;
    return x;
}
int mul(int x, int y) {
    return (x * 1LL * y) % mod;
}
void sadd(int& x, int y) {
    x = add(x, y);
}
void ssub(int& x, int y) {
    x = sub(x, y);
}
void smul(int& x, int y) {
    x = mul(x, y);
}

struct Fenwick {
    int n;
    vector<int> fenw;
    Fenwick() {
        n = 0;
    }
    Fenwick(int _n) {
        n = _n;
        fenw.resize(n);
    }
    void update(int x, int val) {
        for(int i = x; i < n; i += (i & -i)) {
            sadd(fenw[i], val);
        }
    }
    int get(int r) {
        int ans = 0;
        for(int i = r; i >= 1; i -= (i & -i)) {
            sadd(ans, fenw[i]);
        }
        return ans;
    }
    int get(int l, int r) {
        return sub(get(r), get(l - 1));
    }
};

const int N = 1e6 + 10;
int dp[N][3];
int a[N], b[N], c[N];
Fenwick fw[3][2 * N];
vector<int> vals[3][2 * N];
int shift;

int get(int letter, int index, int x) {
    index += shift;
    x = upper_bound(vals[letter][index].begin(), vals[letter][index].end(), x) - vals[letter][index].begin();
    return fw[letter][index].get(x, vals[letter][index].size());
}

void update(int letter, int index, int x, int val) {
    index += shift;
    x = lower_bound(vals[letter][index].begin(), vals[letter][index].end(), x) - vals[letter][index].begin();
    fw[letter][index].update(x, val);
}

int solve(string s) {
    int n = s.size();
    shift = n;
    s = "#" + s;
    a[0] = b[0] = c[0] = 0;
    for(int i = 1; i <= n; i++) {
        a[i] = a[i - 1] + (s[i] == 'a');
        b[i] = b[i - 1] + (s[i] == 'b');
        c[i] = c[i - 1] + (s[i] == 'c');
    }
    for(int i = 0; i <= 2 * n; i++) {
        for(int j = 0; j < 3; j++) {
            vals[j][i].push_back(-1e9);
        }
    }
    for(int i = 1; i <= n; i++) {
        vals[0][b[i] - c[i] + shift].push_back(3 * b[i] - i);
        vals[1][c[i] - a[i] + shift].push_back(3 * c[i] - i);
        vals[2][a[i] - b[i] + shift].push_back(3 * a[i] - i);
    }
    for(int i = 0; i <= 2 * n; i++) {
        for(int j = 0; j < 3; j++) {
            sort(vals[j][i].begin(), vals[j][i].end());
            fw[j][i] = Fenwick(vals[j][i].size() + 1);
        }
    }
    for(int i = 1; i <= n; i++) {
        sadd(dp[i][0], get(0, b[i] - c[i], 3 * b[i] - i));
        sadd(dp[i][1], get(1, c[i] - a[i], 3 * c[i] - i));
        sadd(dp[i][2], get(2, a[i] - b[i], 3 * a[i] - i));
        if(a[i] == b[i] && c[i] > a[i]) sadd(dp[i][2], 1);
        else if(a[i] == c[i] && b[i] > a[i]) sadd(dp[i][1], 1);
        else if(b[i] == c[i] && a[i] > b[i]) sadd(dp[i][0], 1);
        int tot = add(add(dp[i][0], dp[i][1]), dp[i][2]);
        update(0, b[i] - c[i], 3 * b[i] - i, tot);
        update(1, c[i] - a[i], 3 * c[i] - i, tot);
        update(2, a[i] - b[i], 3 * a[i] - i, tot);
    }
    return add(add(dp[n][0], dp[n][1]), dp[n][2]);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    string s;
    cin >> s;
    int n = s.size();
    for(int i = 0; i < n; i++) {
        if(s[i] == 'I') s[i] = 'a';
        else if(s[i] == 'P') s[i] = 'b';
        else s[i] = 'c';
    }
    cout << solve(s);
    return 0;
}