N, M, K = map(int, input().split())
a = 1+K//2
b = (K+1)//2

if K == 0:
    if N > 0 and M > 0:
        print(-1)
    elif N > 0:
        print("".join(map(str, [0] * N)))
    else:
        print("".join(map(str, [1] * M)))
    exit()

if N >= a and M >= b:
    if K % 2 == 0:
        # 0010110
        ans = [0]*(N-b) + [1, 0]*(b-1) + [1]*(M-(b-1)) + [0]
    else:
        # 001011
        ans = [0]*(N-b+1) + [1, 0]*(b-1) + [1]*(M-(b-1))
    print("".join(map(str, ans)))
elif M >= a and N >= b:
    if K % 2 == 0:
        # 1001011
        ans = [1] + [0]*(N-(b-1)) + [1, 0] * (b-1) + [1]*(M-b)
    else:
        # 10010110
        ans = [1] + [0]*(N-b) + [1, 0] * (b-1) + [1]*(M-b) + [0]
    print("".join(map(str, ans)))
else:
    print(-1)