import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;

public class Main {
	static InputStream is;
	static PrintWriter out;
	static String INPUT = "";
	
	static void solve()
	{
		char[] s = ns().toCharArray();
		int n = s.length;
		int par = 0;
		for(char c : s) {
			par += c-'a';
		}
		par %= 3;
		
		int same = 0;
		for(int i = 0;i < n-1;i++) {
			if(s[i] == s[i+1]) {
				same++;
			}
		}
		if(same == n-1) {
			out.println(1);
			return;
		}
		
		if(n == 3 && par == 0) {
			out.println(3);
			return;
		}
		
		long[][][] dp = new long[2][3][3];
		dp[0][0][0] = 1;
		int mod = 998244353;
		for(int i = 0;i < n;i++) {
			long[][][] ndp = new long[2][3][3]; // same last sum
			for(int j = 0;j < 2;j++) {
				for(int k = 0;k < 3;k++) {
					for(int m = 0;m < 3;m++) {
						for(int l = 0;l < 3;l++) {
							int nj = (k == l && i > 0 ? 1 : 0) | j;
							int nk = l;
							int nm = (m+l)%3;
							ndp[nj][nk][nm] += dp[j][k][m];
							if(ndp[nj][nk][nm] >= mod)ndp[nj][nk][nm] -= mod;
						}
					}
				}
			}
			dp = ndp;
		}
		out.println((dp[1][0][par] + dp[1][1][par] + dp[1][2][par] + (same == 0 ? 1 : 0)) % mod);
		
//		Set<String> set = new TreeSet<>();
//		set.add("caca");
//		outer:
//		while(true) {
//			for(String s : set) {
//				for(int i = 0;i < s.length()-1;i++) {
//					if(s.charAt(i) != s.charAt(i+1)) {
//						char x = (char)(s.charAt(i) ^ s.charAt(i+1) ^ 'a' ^ 'b' ^ 'c');
//						char[] ss = s.toCharArray();
//						ss[i] = ss[i+1] = x;
//						String t = new String(ss);
//						if(set.add(t))continue outer;
//					}
//				}
//			}
//			break;
//		}
//		// 20 20 19
//		tr(set);
//		tr(set.size());
	}
	
	public static void main(String[] args) throws Exception
	{
		long S = System.currentTimeMillis();
		is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes());
		out = new PrintWriter(System.out);
		
		solve();
		out.flush();
		long G = System.currentTimeMillis();
		tr(G-S+"ms");
	}
	
	private static boolean eof()
	{
		if(lenbuf == -1)return true;
		int lptr = ptrbuf;
		while(lptr < lenbuf)if(!isSpaceChar(inbuf[lptr++]))return false;
		
		try {
			is.mark(1000);
			while(true){
				int b = is.read();
				if(b == -1){
					is.reset();
					return true;
				}else if(!isSpaceChar(b)){
					is.reset();
					return false;
				}
			}
		} catch (IOException e) {
			return true;
		}
	}
	
	private static byte[] inbuf = new byte[1024];
	static int lenbuf = 0, ptrbuf = 0;
	
	private static int readByte()
	{
		if(lenbuf == -1)throw new InputMismatchException();
		if(ptrbuf >= lenbuf){
			ptrbuf = 0;
			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
			if(lenbuf <= 0)return -1;
		}
		return inbuf[ptrbuf++];
	}
	
	private static boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
//	private static boolean isSpaceChar(int c) { return !(c >= 32 && c <= 126); }
	private static int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }
	
	private static double nd() { return Double.parseDouble(ns()); }
	private static char nc() { return (char)skip(); }
	
	private static String ns()
	{
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while(!(isSpaceChar(b))){
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
	
	private static char[] ns(int n)
	{
		char[] buf = new char[n];
		int b = skip(), p = 0;
		while(p < n && !(isSpaceChar(b))){
			buf[p++] = (char)b;
			b = readByte();
		}
		return n == p ? buf : Arrays.copyOf(buf, p);
	}
	
	private static char[][] nm(int n, int m)
	{
		char[][] map = new char[n][];
		for(int i = 0;i < n;i++)map[i] = ns(m);
		return map;
	}
	
	private static int[] na(int n)
	{
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		return a;
	}
	
	private static int ni()
	{
		int num = 0, b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
	private static long nl()
	{
		long num = 0;
		int b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
	private static void tr(Object... o) { if(INPUT.length() != 0)System.out.println(Arrays.deepToString(o)); }
}


Measured memory_bytes: 63772