import sys

# sys.setrecursionlimit(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
inf = (1 << 63)-1
# inf = (1 << 31)-1
md = 10**9+7
# md = 998244353

n,m,k=LI()

l=(k+1)//2
r=k+1-l

if min(n,m)<l or max(n,m)<r:
    print(-1)
    exit()

if n and m and k==0:
    print(-1)
    exit()

if n>=r:
    k2=(k+1)//2
    ans=[0,1]*k2
    ans+=[1]*(m-k2)
    if k&1==0:
        ans.append(0)
        n-=1
    ans=[0]*(n-k2)+ans
else:
    ans=[1,0]*n
    ans+=[1]*(m-n)

print(*ans,sep="")