#include <iostream>
#include <iomanip>

int main(void)
{
  std::cin.tie(0);
  std::ios::sync_with_stdio(false);
  std::cout << std::fixed << std::setprecision(8);
  int g, c, p;
  std::string s;
  std::cin >> g >> c >> p >> s;
  int fc[3];
  std::fill(fc, fc+3, 0);
  for (auto h : s) {
    if (h=='G') fc[2]++;
    if (h=='C') fc[0]++;
    if (h=='P') fc[1]++;
  }
  int ans = 0;
  if (g > fc[0]) {ans+=fc[0]; g-=fc[0]; fc[0]=0;}
  else {ans+=g; fc[0]-=g; g=0;}
  if (c > fc[1]) {ans+=fc[1]; c-=fc[0]; fc[1]=0;}
  else {ans+=c; fc[1]-=c; c=0;}
  if (p > fc[2]) {ans+=fc[2]; p-=fc[2]; fc[2]=0;}
  else {ans+=p; fc[2]-=p; p=0;}
  ans*=3;
  ans+= std::min(g, fc[2]) + std::min(c, fc[0]) + std::min(p, fc[1]);
  std::cout << ans << std::endl;
  return 0;
}