import java.io.*; import java.util.*; import java.util.stream.*; public class Main { static int[][] dp; static ArrayList values = new ArrayList<>(); static int a; static int b; public static void main(String[] args) throws Exception { Scanner sc = new Scanner(); int n = sc.nextInt(); a = sc.nextInt(); b = sc.nextInt(); char[] inputs = sc.next().toCharArray(); int count = 0; int max = 0; for (int i = 0; i + 2 < n; i++) { if (inputs[i] == 'c' && inputs[i + 1] == 'o' && inputs[i + 2] == 'n') { count++; i += 2; } else { if (count / a > 0 || count / b > 0) { values.add(count); max += count / a; } count = 0; } } if (count / a > 0 || count / b > 0) { values.add(count); max += count / a; } dp = new int[values.size()][max + 1]; for (int[] arr : dp) { Arrays.fill(arr, -1); } int ans = 0; for (int i = max; i >= 0; i--) { int x = dfw(values.size() - 1, i); int current = Math.min(i, x) * 2; if (i > x) { current++; } ans = Math.max(ans, current); } System.out.println(ans); } static int dfw(int idx, int v) { if (idx < 0) { if (v == 0) { return 0; } else { return Integer.MIN_VALUE; } } if (dp[idx][v] < 0) { dp[idx][v] = Integer.MIN_VALUE; int x = values.get(idx); for (int i = 0; i * a <= x && i <= v; i++) { dp[idx][v] = Math.max(dp[idx][v], dfw(idx - 1, v - i) + (x - i * a) / b); } } return dp[idx][v]; } } class Utilities { static String arrayToLineString(Object[] arr) { return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n")); } static String arrayToLineString(int[] arr) { return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new)); } } class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); StringBuilder sb = new StringBuilder(); public Scanner() throws Exception { } public int nextInt() throws Exception { return Integer.parseInt(next()); } public long nextLong() throws Exception { return Long.parseLong(next()); } public double nextDouble() throws Exception { return Double.parseDouble(next()); } public int[] nextIntArray() throws Exception { return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray(); } public String next() throws Exception { while (!st.hasMoreTokens()) { st = new StringTokenizer(br.readLine()); } return st.nextToken(); } }