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

if min(M,N)*2-(M==N)<K:
    print(-1)
    exit()

if K%2==1:
    K-=1
    n=K//2
    print("0"*(N-n)+"10"*n+"1"*(M-n))
else:
    K-=2
    n=K//2
    print("0"*(N-n-1)+"10"*n+"1"*(M-n)+"0")