// {{{ by unolight
#include <bits/stdc++.h>
#include <unistd.h>
#pragma GCC diagnostic ignored "-Wunused-result"
#define SZ(x) ((int)(x).size())
#define ALL(x) begin(x),end(x)
#define RALL(x) rbegin(x),rend(x)
#define REP(i,n) for ( int i=0; i<int(n); i++ )
#define REP1(i,a,b) for ( int i=(a); i<=int(b); i++ )
#define MP make_pair
#define PB push_back
using namespace std;
typedef int64_t LL;
typedef pair<int,int> PII;
typedef vector<int> VI;

template<class T> void _R( T &x ) { cin>>x; }
void _R( int &x ) { scanf("%d",&x); }
void _R( int64_t &x ) { scanf("%" PRId64,&x); }
void _R( double &x ) { scanf("%lf",&x); }
void _R( char &x ) { scanf(" %c",&x); }
void _R( char *x ) { scanf("%s",x); }
void R() {}
template<class T, class... U> void R( T& head, U&... tail ) { _R(head); R(tail...); }

template<class T> void _W( const T &x ) { cout<<x; }
void _W( const int &x ) { printf("%d",x); }
void _W( const int64_t &x ) { printf("%" PRId64,x); }
void _W( const double &x ) { printf("%.16f\n",x); }
void _W( const char &x ) { putchar(x); }
void _W( const char *x ) { printf("%s",x); }
template<class T> void _W( const vector<T> &x ) { for (auto i = x.begin(); i != x.end(); _W(*i++)) if (i != x.cbegin()) putchar(' '); }
void W() {}
template<class T, class... U> void W( const T& head, const U&... tail ) { _W(head); putchar(sizeof...(tail)?' ':'\n'); W(tail...); }

template<class T> inline bool chmax( T &a, const T &b ) { return b>a ? a=b,true : false; }
template<class T> inline bool chmin( T &a, const T &b ) { return b<a ? a=b,true : false; }
template<class T, class F=less<T>> void sort_uniq( vector<T> &v, F f=F() ) {
    sort(begin(v),end(v),f);
    v.resize(unique(begin(v),end(v))-begin(v));
}

template<class T> using MaxHeap = priority_queue<T>;
template<class T> using MinHeap = priority_queue<T, vector<T>, greater<T>>;

#ifdef UNO
template<class T> void _dump(const char *s, T &&head) { cerr << s << "=" << head << endl; }
template<class T, class... Args> void _dump(const char *s, T &&head, Args &&... tail) {
    for (int c = 0; *s != ',' || c != 0; cerr << *s++) {
        if (*s == '(' || *s == '[' || *s == '{') c++;
        if (*s == ')' || *s == ']' || *s == '}') c--;
    }
    cerr << "=" << head << ", ";
    _dump(s + 1, tail...);
}
#define dump(...) do { fprintf(stderr, "%s:%d - ", __PRETTY_FUNCTION__, __LINE__); _dump(#__VA_ARGS__, __VA_ARGS__); } while (0)

template<class Iter> ostream &_out(ostream &s, Iter b, Iter e) {
    s << "[";
    for (auto it = b; it != e; it++) s << (it == b ? "" : " ") << *it;
    return s << "]";
}

template<class A, class B> ostream &operator<<(ostream &s, const pair<A, B> &p) { return s << "(" << p.first << "," << p.second << ")"; }
template<class T> ostream &operator<<(ostream &s, const vector<T> &c) { return _out(s, ALL(c)); }
template<class T, size_t N> ostream &operator<<(ostream &s, const array<T, N> &c) { return _out(s, ALL(c)); }
template<class T> ostream &operator<<(ostream &s, const set<T> &c) { return _out(s, ALL(c)); }
template<class A, class B> ostream &operator<<(ostream &s, const map<A, B> &c) { return _out(s, ALL(c)); }
#else
#define dump(...)
#endif
// }}}

const int MAX_N=100010;
const int Z=1e9;
int n, K, r, s, p;
char T[MAX_N];

void solve() {
    int ans=0;
    bool win[MAX_N]={};

    for(int i = 0; i < n; i++) {
        if(i < K || T[i-K] != T[i] || !win[i-K]) win[i] = true;
        if(win[i]) {
            if(T[i]=='r') ans += p;
            if(T[i]=='p') ans += s;
            if(T[i]=='s') ans += r;
        }
    }

    W(ans);
}

void solve2() {
    // max score end with p, s, r at i%K
    VI dpp(K,0), dps(K, 0), dpr(K, 0);

    for(int i=0; i<n; i++) {
        int tp = dpp[i%K], ts = dps[i%K], tr = dpr[i%K];
        if(T[i] == 's') {
            dpr[i%K] = max(tp, ts) + r;
            dpp[i%K] = max(tr, ts);
            dps[i%K] = max(tr, tp);
        }
        if(T[i] == 'r') {
            dpr[i%K] = max(tp, ts);
            dpp[i%K] = max(tr, ts) + p;
            dps[i%K] = max(tr, tp);
        }
        if(T[i] ==  'p') {
            dpr[i%K] = max(tp, ts);
            dpp[i%K] = max(tr, ts);
            dps[i%K] = max(tr, tp) + s;
        }
    }
    int ans = 0;
    REP(i, K) ans += max(dpp[i], max(dps[i], dpr[i]));

    W(ans);
}

int main() {
    R(n,K,r,s,p);
    R(T);
    // solve1(); // greedy
    solve2();    // dp
    return 0;
}

Measured memory_bytes: 1408