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

    if K==0:
        if N==0:
            return "1"*M
        elif M==0:
            return "0"*N
        else:
            return -1

    Ans="2"
    if K%2==0:
        if (N>=K//2+1) and (M>=K//2):
            X=["0" if k%2==0 else "1" for k in range(K+1)]
            X[0]+="0"*(N-(K//2+1))
            X[-2]+="1"*(M-K//2)
            Ans=min(Ans, "".join(X))
        if (N>=K//2) and (M>=K//2+1):
            X=["1" if k%2==0 else "0" for k in range(K+1)]
            X[1]+="0"*(N-K//2)
            X[-1]+="1"*(M-(K//2+1))
            Ans=min(Ans, "".join(X))
    else:
        if (N>=(K+1)//2) and (M>=(K+1)//2):
            X=["0" if k%2==0 else "1" for k in range(K+1)]
            X[0]+="0"*(N-(K+1)//2)
            X[-2]+="1"*(M-(K+1)//2)
            Ans=min(Ans, "".join(X))
    return Ans if Ans!="2" else -1


#==================================================
print(solve())