#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}()); 
const ll mod=998244353;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=1010000;
char ps[N];
int dp[N],s[N][3];
PII pt[N];
void solve(int l,int r) {
	if (l==r) {
		return;
	}
	int md=(l+r)>>1;
	solve(l,md);
	rep(ex,0,3) {
		rep(p1,0,3) if (p1!=ex) rep(p2,p1+1,3) if (p2!=ex) {
			vector<pair<PII,int>> vl;
			rep(i,l,md+1) {
				pt[i]=mp(s[i][p2]-s[i][p1],s[i][ex]-s[i][p1]);
				//printf("? %d %d\n",i,dp[i]);
				vl.pb(mp(pt[i],dp[i]));
			}
			sort(all(vl));
			rep(i,0,SZ(vl)) if (i>0&&vl[i].fi.fi==vl[i-1].fi.fi) vl[i].se=(vl[i].se+vl[i-1].se)%mod;
			//printf("! %d\n",vl[0].se);
			rep(i,md+1,r+1) {
				pt[i]=mp(s[i][p2]-s[i][p1],s[i][ex]-s[i][p1]);
				auto it=upper_bound(all(vl),mp(pt[i],-1));
				if (it!=vl.begin()) {
					--it;
					if (it->fi.fi==pt[i].fi) dp[i]=(dp[i]+it->se)%mod;
				}
			}
		}
	}
	solve(md+1,r);
}
int main() {
	scanf("%s",ps+1);
	int n=strlen(ps+1);
	rep(i,1,n+1) {
		rep(j,0,3) s[i][j]=s[i-1][j];
		int w=ps[i]=='I'?0:(ps[i]=='C'?1:2);
		s[i][w]++;
	}
	dp[0]=1;
	solve(0,n);
	printf("%d\n",dp[n]);
}