n, m = map(int, input().split())
g = [[] for _ in range(n)]
for e in range(m):
  a, b = map(int, input().split())
  g[a].append((b, e))

ans = ["0" for _ in range(n)]
used = [False for _ in range(m)]
for u in range(n - 1, -1, -1):
  for v, e in g[u]:
    if used[e]:
      continue
    used[e] = True
    if ans[v] == "0":
      ans[u] = "1"

while len(ans) > 1 and ans[-1] == "0":
  ans.pop()

print(''.join(reversed(ans)))