#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <queue>
#include <list>
#include <stack>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;

int main(){
  int G, C, P;
  string S;
  cin >> G >> C >> P;
  cin >> S;

  int sum = 0;
  string ret(S.length(), '*');
  rep(i,S.length()){
    if(S[i]=='C' && G>0){ ret[i]='G'; G--; sum+=3; }
    else if(S[i]=='P' && C>0){ ret[i]='C'; C--; sum+=3; }
    else if(S[i]=='G' && P>0){ ret[i]='P'; P--; sum+=3; }
  }
  rep(i,S.length()){
    if(ret[i] != '*') continue;
    if(S[i]=='C' && C>0){ ret[i]='C'; C--; sum++; }
    else if(S[i]=='P' && P>0){ ret[i]='P'; P--; sum++; }
    else if(S[i]=='G' && G>0){ ret[i]='G'; G--; sum++; }
  }

  cout << sum << endl;
  return 0;
}