N, M, K = gets.split.map(&:to_i)

def f(n, m, k)
  zero_stack = []
  one_stack = []

  (k + 1).times do |i|
    if i.even?
      zero_stack << 1
    else
      one_stack << 1
    end
  end

  if zero_stack.size > n
    return false
  end

  if one_stack.size > m
    return false
  end

  zero_stack[0] += n - zero_stack.size if zero_stack.size > 0
  one_stack[-1] += m - one_stack.size if one_stack.size > 0

  res = ''
  i = 0

  while zero_stack.size > 0 || one_stack.size > 0
    if i.even?
      res << '0' * zero_stack.shift
    else
      res << '1' * one_stack.shift
    end

    i += 1
  end

  res
end

def g(n, m, k)
  zero_stack = []
  one_stack = []

  (k + 1).times do |i|
    if i.even?
      one_stack << 1
    else
      zero_stack << 1
    end
  end

  if zero_stack.size > n
    return false
  end

  if one_stack.size > m
    return false
  end

  zero_stack[0] += n - zero_stack.size if zero_stack.size > 0
  one_stack[-1] += m - one_stack.size if one_stack.size > 0

  res = ''
  i = 0

  while zero_stack.size > 0 || one_stack.size > 0
    if i.even?
      res << '1' * one_stack.shift
    else
      res << '0' * zero_stack.shift
    end

    i += 1 end

  res
end

res1 = f(N, M, K)
res2 = g(N, M, K)
ans = []
ans << res1 if res1
ans << res2 if res2

if ans.empty?
  puts -1
else
  puts ans.sort.first
end