N, M, K = map(int, input().split())

if K == 0:
    if M == 0:
        print("0"*N)
    elif N == 0:
        print("1"*M)
    else:
        print(-1)
    exit()
else:
    cnt = min(N, M)*2
    if N == M: cnt -= 1
    if cnt < K:
        exit(print(-1))

r = K%2
if K-(r^1) <= min(N, M)*2-1 and (r == 1 or K//2+1 <= N):
    cnt = K-(r^1)
    c = (cnt+1)//2
    MID = "01"*c
    N -= c
    M -= c
    if r == 1:
        L = "0"*N
        R = "1"*M
    else:
        L = "0"*(N-1)
        R = "1"*M+"0"
    print(L+MID+R)
else:
    L = "1"+"01"*(K//2)
    R = "1"*(N+M-len(L))
    print(L+R)