n, A, B = map(int, input().split())
s = input().strip()

runs = []
i = 0
while i <= len(s) - 3:
    if s[i:i+3] == 'con':
        count = 1
        i += 3
        while i <= len(s) - 3 and s[i:i+3] == 'con':
            count += 1
            i += 3
        runs.append(count)
    else:
        i += 1

total = 0

for l in runs:
    steps = 0
    current_parity = 1  # 1 for A's turn, 0 for B's turn
    remaining = l
    while True:
        if current_parity == 1:
            if remaining >= A:
                steps += 1
                remaining -= A
                current_parity = 0
            else:
                break
        else:
            if remaining >= B:
                steps += 1
                remaining -= B
                current_parity = 1
            else:
                break
    total += steps

print(total)