N,M,K = map(int,input().split()) import sys 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 + 1) else: ans = S[:-1] + "1" * (M - m) + "0" print(ans) else: print(-1)