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

def solve(N,M,K):
    if min(M,N)*2-(M==N)<K or K==0 and min(N,M)>0:
        return "-1"
    if K%2==1:
        K-=1
        n=K//2
        return ("0"*(N-n)+"10"*n+"1"*(M-n))
    else:
        if K==0:
            if N:return "0"*N
            return "1"*M
        K-=2
        n=K//2
        if N-n-1>0:
            return ("0"*(N-n-1)+"10"*n+"1"*(M-n)+"0")
        else:
            return ("10"*(n+1)+"1"*(M-n-1))
print(solve(N,M,K))