def RLE(A):
    tmp = [[A[0],0]]
    now = 0
    for i in range(len(A)):
        if tmp[now][0] == A[i]:
            tmp[now][1] += 1
        else:
            tmp.append([A[i],1])
            now += 1
    return tmp

def main():
    N = int(input())
    S = input()

    r = RLE(S)
    ans = []
    cnt = 0

    for s,c in r:
        if s == "o":
            ans.append(cnt+1) 
        cnt += c

    print(len(ans))
    print(*ans)


if __name__ == "__main__":
    main()