let inpt = readLine()!

var cur = inpt

var ans = 0

while(cur.count >= 3) {
    ans *= 2
    if cur.prefix(4) == "hamu" {
        ans += 1
        cur = String(cur.suffix(cur.count - 4))
    } else {
        cur = String(cur.suffix(cur.count-3))
    }
}

print(ans)