#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define vtpl(x,y,z) vector<tuple<x,y,z>>
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[9]={0,1,-1,0,1,1,-1,-1,0};
const ll dx[9]={1,0,0,-1,1,-1,1,-1,0};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
ll dp[310][310][310];//iもじめまで見て、gをあとjかい、cをあとkかい出せる
int main(){
    ll g,c,sc;cin >> g >> c >>sc;
    ll n=g+c+sc;
    string s;cin >> s;
    rep(i,310)rep(j,310)rep(k,310)dp[i][j][k]=-INF;
    dp[0][g][c]=0;
    rep(i,s.size()){
        rep(j,310){
            rep(k,310){
                if(dp[i][j][k]==-INF)continue;
                ll p=n-i-j-k;if(p<0)continue;
                if(s[i]=='G'){
                    if(j>=1)chmax(dp[i+1][j-1][k],dp[i][j][k]+1);
                    if(k>=1)chmax(dp[i+1][j][k-1],dp[i][j][k]);
                    if(p>=1)chmax(dp[i+1][j][k],dp[i][j][k]+3);
                }
                if(s[i]=='C'){
                    if(j>=1)chmax(dp[i+1][j-1][k],dp[i][j][k]+3);
                    if(k>=1)chmax(dp[i+1][j][k-1],dp[i][j][k]+1);
                    if(p>=1)chmax(dp[i+1][j][k],dp[i][j][k]);
                }
                if(s[i]=='P'){
                    if(j>=1)chmax(dp[i+1][j-1][k],dp[i][j][k]);
                    if(k>=1)chmax(dp[i+1][j][k-1],dp[i][j][k]+3);
                    if(p>=1)chmax(dp[i+1][j][k],dp[i][j][k]+1);
                }
            }
        }
    }
    ll ans=0;
    rep(i,310)rep(k,310){
        chmax(ans,dp[s.size()][i][k]);
    }
    cout << ans <<endl;
}