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

import sys
if K == 0:
	if N * M == 0:
		print("0"* N + "1" * M)
	else:
		print(-1)
	exit()

if N >= (K + 2) // 2 and M >= (K + 1) // 2:
	n = (K + 2) // 2
	m = (K + 1) // 2
	S = "01" * m
	if n > m:
		ans = "0" *(N - n) + S + "1" * (M - m) + "0"
	else:
		ans = "0" * (N - n) + S + "1" * (M - m)
	print(ans)
elif N >= (K + 1) // 2 and M >= (K + 2) // 2:
	n = (K + 1) // 2
	m = (K + 2) // 2
	S = "10" * n
	if m > n:
		ans = S + "1" * (M - m)
	else:
		ans = S[:-1] + "1" * (M - m) + "0"
	print(ans)
else:
	print(-1)