N,M,K = map(int,input().split())
if K==0:
    if N==M==0:
        S = ""
        print(S)
    elif N==0:
        S = "1"*M
        print(S)
    elif M==0:
        S = "0"*N
        print(S)
    else:
        print(-1)
elif N==M:
    if K>=2*N:
        print(-1)
    else:
        if K%2==1:
            S = "0"*(N-K//2)+"10"*(K//2)+"1"*(M-K//2)
        else:
            S = "0"*(N-K//2)+"10"*(K//2-1)+"1"*(M-K//2+1)+"0"
        print(S)
elif N>M:
    if K>2*M:
        print(-1)
    else:
        if K%2==1:
            S = "0"*(N-K//2)+"10"*(K//2)+"1"*(M-K//2)
        else:
            S = "0"*(N-K//2)+"10"*(K//2-1)+"1"*(M-K//2+1)+"0"
        print(S)
else:
    if K>2*N:
        print(-1)
    else:
        if K%2==1:
            S = "0"*(N-K//2)+"10"*(K//2)+"1"*(M-K//2)
        elif K<2*N:
            S = "0"*(N-K//2)+"10"*(K//2-1)+"1"*(M-K//2+1)+"0"
        else:
            S = "10"*N+"1"*(M-N)
        print(S)