S=input()
K=int(input())
mod=998244353
def f(x):
  if type(x)==type(0):
    r=[0]*3
    if x==3:
      return (1,1,1)
    r[x]=1
    return tuple(r)
  return x

def mAx(a,b):
  r=[0]*3
  a=f(a)
  b=f(b)
  for i in range(3):
    for j in range(3):
      r[max(i,j)]=(r[max(i,j)]+a[i]*b[j])%mod
  return tuple(r)

def mex(a,b):
  if min(a,b)>0:
    return 0
  elif a==0 and b==0:
    return 1
  elif max(a,b)<2:
    return 2
  else:
    return 1

MEX=[[mex(i,j) for j in range(3)]for i in range(3)]

def mEx(a,b):
  a=f(a)
  b=f(b)
  r=[0]*3
  for i in range(3):
    for j in range(3):
      r[MEX[i][j]]=(r[MEX[i][j]]+a[i]*b[j])%mod
  return tuple(r)

def m3x(a,b):
  a=f(a)
  b=f(b)
  r=[0]*3
  for i in range(3):
    for j in range(3):
      r[MEX[i][j]]=(r[MEX[i][j]]+a[i]*b[j])%mod
      r[max(i,j)]=(r[max(i,j)]+a[i]*b[j])%mod
  return tuple(r)

import sys
sys.setrecursionlimit(1000000)
S=S.replace('a','A').replace('e','E').replace('?','3')
print(f(eval(S))[K])