import itertools
'''
K+1個のブロック
a_0,...,a_K
a_i>=1

a_{2i}個の0
a_{2i+1}個の1
辞書順最小にするためには
a_0を極力大きく
a_2,a_4,...,a_{2i}を1
'''

n,m,k=map(int,input().split())
def solve(N,M,K):
    if K==0:
        if N*M>0:
            return(-1)
        else:
            return("0"*N+"1"*M)
    Ncash=N
    Mcash=M
    A=[0 for i in range(K+1)]
    for i in range(1,K+1,2):
        A[i]+=1
        M-=1
    if M<0:
        return -1
    A[K-(K+1)%2]+=M
    for i in range(0,K+1,2):
        A[i]+=1
        N-=1
    if N<0:
        N=Ncash
        M=Mcash
        B=[0 for i in range(K+1)]
        for i in range(0,K+1,2):
            B[i]+=1
            M-=1
        if M<0:
            return -1
        B[K-K%2]+=M
        for i in range(1,K+1,2):
            B[i]+=1
            N-=1
        if N<0:
            return -1
        B[1]+=N
        res=[]
        for i in range(K+1):
            res.append(str((i+1)%2)*B[i])
        return "".join(res)
    else:
        A[0]+=N
    res=[]
    for i in range(K+1):
        res.append(str(i%2)*A[i])
    return "".join(res)
def solve_naive(N,M,K):
    ans=[]
    for seq in itertools.combinations(range(N+M),M):
        res=[0 for i in range(N+M)]
        for i in seq:
            res[i]=1
        cnt=0
        for i in range(N+M-1):
            if res[i]!=res[i+1]:
                cnt+=1
        if cnt==K:
            ans.append(res)
    if len(ans)==0:
        return -1
    else:
        return "".join([str(x) for x in min(ans)])
import random
print(solve(n,m,k))
#print(solve_naive(n,m,k))
exit()
while(True):
    n=random.randrange(5)
    m=random.randrange(5)
    k=random.randrange(10)
    ans1=solve(n,m,k)
    ans2=solve_naive(n,m,k)
    if ans1!=ans2:
        print(ans1,ans2,n,m,k)
        break