import sys

def read_data():
    n, m = map(int, input().split())
    Es = [[] for v in range(n)]
    for line in sys.stdin:
        a, b = map(int, line.split())
        Es[a].append(b)
    return n, m, Es

def solve(n, m, Es):
    used = [0] * n
    for v in range(n - 1, -1, -1):
        for u in Es[v]:
            if not used[u]:
                used[v] = 1
                break
    while not used[-1]:
        used.pop()
    used.reverse()
    return ''.join(map(str, used))

n, m, Es = read_data()
print(solve(n, m, Es))