#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<ll, ll> P;
typedef pair<int, int> Pi;
typedef vector<ll> Vec;
typedef vector<int> Vi;
typedef vector<string> Vs;
typedef vector<vector<ll>> VV;
typedef vector<vector<int>> VVi;

#define REP(i, a, b) for(ll i=(a); i<(b); i++)
#define PER(i, a, b) for(ll i=(a); i>=(b); i--)
#define rep(i, n) REP(i, 0, n)
#define per(i, n) PER(i, n, 0)
const ll INF=1e18+18;
const ll MAX=100005;
const ll MOD=1000000007;
#define Yes(n) cout << ((n) ? "Yes" : "No") << endl;
#define YES(n) cout << ((n) ? "YES" : "NO") << endl;
#define ALL(v) v.begin(), v.end()
#define rALL(v) v.rbegin(), v.rend()
#define pb(x) push_back(x)
#define mp(a, b) make_pair(a,b)
#define Each(a,b) for(auto &a :b)
#define REPM(i, mp) for (auto i = mp.begin(); i != mp.end(); ++i)
#define dbg(x_) cerr << #x_ << ":" << x_ << endl;
#define dbgmap(mp) cerr << #mp << ":"<<endl; for (auto i = mp.begin(); i != mp.end(); ++i) { cerr << i->first <<":"<<i->second << endl;}
#define dbgarr(n,m,arr) rep(i,n){rep(j,m){cerr<<arr[i][j]<<" ";}cerr<<endl;}
#define dbgdp(n,arr) rep(i,n){cerr<<arr[i]<<" ";}cerr<<endl;
#define sum(v) accumulate(ALL(v),0)
#define fi first
#define se second

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return true; } return false; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return true; } return false; }

template<typename T1, typename T2>
ostream &operator<<(ostream &s, const pair<T1, T2> &p) { return s<<"("<<p.first<<", "<<p.second<<")"; }

// vector
template<typename T>
ostream &operator<<(ostream &s, const vector<T> &v) {
    int len=v.size();
    for(int i=0; i<len; ++i) {
        s<<v[i];
        if(i<len-1) s<<"	";
    }
    return s;
}

// 2 dimentional vector
template<typename T>
ostream &operator<<(ostream &s, const vector<vector<T> > &vv) {
    int len=vv.size();
    for(int i=0; i<len; ++i) {
        s<<vv[i]<<endl;
    }
    return s;
}


int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    cout<<std::setprecision(10);

    ll n,k;
    ll r,s,p;
    cin>>n>>k>>r>>s>>p;
    string t;
    cin>>t;
    vector<string> v(k);

    rep(i,n){
        v[i%k].pb(t[i]);
    }

    ll ans=0;

    rep(i,k){
        string &x = v[i];
        if(x.length()==0)continue;
        ll m = x.length();
        VVi dp(m,Vi(3));
        rep(j,m){
            char &y = x[j];
            ll win = -1;
            ll score = 0;
            if(y=='r'){
                win = 2;
                score = p;
            }
            if(y=='s'){
                win = 0;
                score = r;
            }
            if(y=='p'){
                win = 1;
                score = s;
            }
            if(j>0){
                dp[j][0] = max(dp[j-1][1],dp[j-1][2]);
                dp[j][1] = max(dp[j-1][0],dp[j-1][2]);
                dp[j][2] = max(dp[j-1][1],dp[j-1][0]);
                dp[j][win] += score;
            }else{
                dp[j][win] += score;
            }
        }
        int add=0;
        rep(j,3){
            chmax(add,dp[m-1][j]);
        }
        ans += add;
    }


    cout<<ans<<endl;
    return  0;
}


Measured memory_bytes: 5888