#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
using namespace std;

int main(void){
  int g, c, p;
  string s;
  cin >> g >> c >> p >> s;
  int eg, ec, ep;
  eg = ec = ep = 0;
  for(int i = 0; i < s.length(); i++){
    if(s[i] == 'G') eg++;
    if(s[i] == 'C') ec++;
    if(s[i] == 'P') ep++;
  }
  int ans = 0;
  int temp;
  temp = min(g, ec);
  ans += temp * 3;
  g -= temp;
  ec -= temp;
  temp = min(c, ep);
  ans += temp * 3;
  c -= temp;
  ep -= temp;
  temp = min(p, eg);
  ans += temp * 3;
  p -= temp;
  eg -= temp;
  temp = min(g, eg);
  ans += temp;
  temp = min(c, ec);
  ans += temp;
  temp = min(p, ep);
  ans += temp;
  cout << ans << endl;
  return 0;
}