#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <tuple>
#include <cmath>
#include <numeric>
#include <functional>
#include <cassert>

#define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl;
#define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using namespace std;
typedef long long ll;

template<typename T>
vector<vector<T>> vec2d(int n, int m, T v){
    return vector<vector<T>>(n, vector<T>(m, v));
}

template<typename T>
vector<vector<vector<T>>> vec3d(int n, int m, int k, T v){
    return vector<vector<vector<T>>>(n, vector<vector<T>>(m, vector<T>(k, v)));
}

template<typename T>
void print_vector(vector<T> v, char delimiter=' '){
    if(v.empty()) {
        cout << endl;
        return;
    }
    for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter;
    cout << v.back() << endl;
}

int dp[20000];

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    int n, a, b; cin >> n >> a >> b;
    string s; cin >> s;
    vector<int> v;
    for(int i = 0; i*3 <= n; i++) dp[i] = -1;
    for(int i = 0; i < n;){
        int r = i+1;
        int j = i;
        while(s.substr(j, 3) == "con"){
            j += 3;
        }
        chmax(r, j);
        if(r > i+1){
            v.push_back((r-i)/3);
        }
        i = r;
    }
    dp[0] = 0;
    int r = 0;
    for(int x: v){
        int rr = x/a;
        for(int i = r; i >= 0; i--){
            for(int p = rr; p >= 0; p--){
                int q = (x-p*a)/b;
                chmax(dp[i+p], dp[i]+q);
            }
        }
        r += rr;
    }
    // print_vector(v);
    int ans = 0;
    for(int p = 1; p*3 <= n; p++){
        if(dp[p] == -1) continue;
        int q = min(p, dp[p]);
        int pp = p;
        if(p > q+1) pp = q+1;
        chmax(ans, pp+q);
    }
    cout << ans << endl;
}