me=gets.split.map(&:to_i)
ec={'G'=>0,'C'=>1,'P'=>2}
en=[0,0,0]
gets.chomp.chars{|c|en[ec[c]]+=1}

pt=0
3.times{|i|
  t=[en[i],me[i-1]].min
  pt+=t*3
  en[i]-=t;me[i-1]-=t
}
3.times{|i|
  t=[en[i],me[i]].min
  pt+=t
  en[i]-=t;me[i]-=t
}
p pt