g,c,p=map(int,input().split())
s=list(input())
g2=s.count('G')
c2=s.count('C')
p2=s.count('P')

ans=0

if p>=g2:
  ans+=g2*3
  p-=g2
  g2=0
else:
  ans+=p*3
  g2-=p
  p=0

if g>=c2:
  ans+=c2*3
  g-=c2
  c2=0
else:
  ans+=g*3
  c2-=g
  g=0

if c>=p2:
  ans+=p2*3
  c-=p2
  p2=0
else:
  ans+=c*3
  p2-=c
  c=0

ans+=min(g,g2)+min(c,c2)+min(p,p2)

print(ans)