// Goods things are coming, just keep believing 
 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
 
using namespace __gnu_pbds;
using namespace std;
 
 
#define FOR(i, x, n) for(ll i = x; i < n; i++) 
#define pb push_back
#define pf push_front
#define ll long long
#define hii cout << "hii" << endl
#define okay cout << "okay" << endl
// #define hey cout << "hey" << endl
#define pii pair<int, int>
#define pll pair<ll, ll>
// #define mpp make_pair
#define endl '\n'
#define ff first 
#define int long long
#define ss second
#define vi vector<int>
#define all(s) s.begin(), s.end()
#define si size()
 #define ld long double
#define INF 1000000000;
 
template <class T> ostream& operator << (ostream &os, const vector<T> &v) { for (T i : v) os << i << ' '; return os; }
template <class T> ostream& operator << (ostream &os, const set<T> &v) { for (T i : v) os << i << ' '; return os; }
template <class T, class S> ostream& operator << (ostream &os, const pair<T, S> &v) { os << v.first << ' ' << v.second; return os; }
template <class T, class S> ostream& operator << (ostream &os, const unordered_map<T, S> &v) { for (auto i : v) os << '(' << i.first << "=>" << i.second << ')' << ' '; return os; } 
 
 
 
#ifndef ONLINE_JUDGE
#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
    template <class Arg1> void __f(const char* name, Arg1&& arg1) { cerr << name << " : " << arg1 << endl; }
    template <class Arg1, class... Args>
    void __f(const char* names, Arg1&& arg1, Args&&... args) {
        const char* sep = strchr(names + 1, ',');
        cerr.write(names, sep - names) << " : " << arg1 << "  ";
        __f(sep + 1, args...);
    }
#else
#define trace(...) 0
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#pragma GCC target("avx2,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define _CRT_SECURE_NO_WARNINGS
#endif // ifndef ONLINE_JUDGE
 
typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;
 
 
 
const int N = 2e5 + 5;
const int LG = 20;
const int mod = 1e9 + 7;

int arr[N];
int pos[N];
vector<int> v[N];

int n, k, r, s, p;
string input;
int DP[N][3];

int f(int idx, int prev)
{
	if(idx >= input.si)
	{
		return 0;
	}
	int & ret = DP[idx][prev];
	if(~ret)
	{
		return ret;
	}
	if(input[idx] == 'r')
	{
		if(prev == 2)
		{
			return ret = max({f(idx + k, 1), f(idx + k, 0)});
		}
		else if(prev == 1)
		{
			return ret = max({f(idx + k, 0), p + f(idx + k, 2)});
		}
		else
		{
			return ret = max({f(idx + k, 1), p + f(idx + k, 2)});
		}
	}
	if(input[idx] == 's')
	{
		if(prev == 0)
		{
			return ret = max({f(idx + k, 1), f(idx + k, 2)});
		}
		else if(prev == 1)
		{
			return ret = max({r + f(idx + k, 0), f(idx + k, 2)});
		}
		else
		{
			return ret = max({r + f(idx + k, 0), f(idx + k, 1)});
		}
	}
	if(input[idx] == 'p')
	{
		if(prev == 1)
		{
			return ret = max({f(idx + k, 2), f(idx + k, 0)});
		}
		else if(prev == 2)
		{
			return ret =  max({s + f(idx + k, 1), f(idx + k, 0)});
		}
		else
		{
			return ret = max({s + f(idx + k, 1), f(idx + k, 2)});
		}
	}
}

void solve()
{
	cin >> n >> k >> r >> s >> p;
	cin >> input;
	int ans = 0;
	memset(DP, -1, sizeof(DP));
	for(int i = 0; i < k; i++)
	{
		ans += max({f(i, 0), f(i, 1), f(i, 2)});
	}
	cout << ans;

}
 
int32_t main()
{
	ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
	int t = 1;
	// cin >> t;
	while(t--)
	{
		solve();
	}
}

Measured memory_bytes: 13776