#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef pair<int,int> P;

int main(){
  int G, C, P;
  string s;
  cin >> G >> C >> P >> s;
  int res = 0;
  int n = sz(s);
  vector<int> win(n,0);
  rep(i,n) {
    if (s[i] == 'G' && P > 0) {
      res += 3;
      P--;
      win[i] = 1;
    }
    if (s[i] == 'C' && G > 0) {
      res += 3;
      G--;
      win[i] = 1;
    }
    if (s[i] == 'P' && C > 0) {
      res += 3;
      C--;
      win[i] = 1;
    }
  }

  rep(i,n) {
    if (!win[i]) {
      if (s[i] == 'G' && G > 0) res++, G--;
      if (s[i] == 'C' && C > 0) res++, C--;
      if (s[i] == 'P' && P > 0) res++, P--; 
    }
  }
  cout << res << endl;
  return 0;
}