n,m,k = map(int,input().split())

if k == 0:
	if n > 0 and m > 0:
		print(-1)
	else:
		if n > 0:
			print("0"*n)
		else:
			print("1"*m)
	exit()

# zero 先頭
zero = k // 2 + 1
one = (k + 1) // 2
if zero <= n and one <= m:
	v = [1] * (k + 1)
	if k % 2 == 1:
		v[0] = n - zero + 1
		v[-1] = m - one + 1
	else:
		v[0] = n - zero + 1
		v[-2] = m - one + 1
	ans = []
	for i in range(k+1):
		for j in range(v[i]):
			if i % 2 == 0:
				ans.append("0")
			else:
				ans.append("1")
	print("".join(ans))
	exit()

# one 先頭
zero = (k + 1) // 2
one = k // 2 + 1
if zero <= n and one <= m:
	v = [1] * (k + 1)
	if k % 2 == 1:
		v[1] = n - zero + 1
		v[-2] = m - one + 1
	else:
		v[1] = n - zero + 1
		v[-1] = m - one + 1
	ans = []
	for i in range(k+1):
		for j in range(v[i]):
			if i % 2 == 1:
				ans.append("0")
			else:
				ans.append("1")
	print("".join(ans))
	exit()

print(-1)