n,a,b=map(int,input().split())
s=["#"]+list(input())
x=[]
l=1
nod=["o","n","c"]
while l<=n:
    if s[l]!="c":l+=1
    else:
        r=l
        while r<n:
            d=(r-l)%3
            if s[r+1]==nod[d]:
                r+=1
            else:
                break
        num=(r-l+1)//3
        if num>0:x.append(num)
        l=r+1
n=len(x)
if n==0:
    print(0)
    exit()
ans=0
for i in range(n):
    num=x[i]//(a+b)
    ans+=2*num
    x[i]-=num*(a+b)
if a==b:
    for i in range(n):
        ans+=x[i]//a
    print(ans)
elif a>b:
    B=0
    AB=0
    for i in range(n):
        if x[i]>=a:AB+=1
        elif x[i]>=b:B+=1
    if AB>=B:
        ans+=AB+B
    else:
        ans+=AB*2
    print(ans)
else:
    A=0
    AB=0
    for i in range(n):
        if x[i]>=b:AB+=1
        elif x[i]>=a:A+=1
    if AB>=A:
        ans+=AB+A
    elif AB+1==A:
        ans+=AB+A
    else:
        ans+=2*AB+1
    print(ans)