input()
vkString = input()
max = vkString.count('VK')
vkString = list(vkString)
for vk in ['V','K']:
    for i in range(0,len(vkString)):
        v = vkString.copy()
        v[i] = vk
        v = ''.join(v)
        count = v.count('VK')
        if count > max:
            max = count
print(max)