Edge Split

Description:

Input:

Each test contains multiple test cases. The first line contains a single integer $$$t$$$ ($$$1 \le t \le 10^5$$$) — the number of test cases. Description of the test cases follows.

The first line of each test case contains two integers $$$n$$$ and $$$m$$$ ($$$2 \le n \le 2 \cdot 10^5$$$; $$$n-1 \leq m \leq \min{\left(n+2,\frac{n \cdot (n-1)}{2}\right)}$$$) — the number of vertices and the number of edges respectively.

$$$m$$$ lines follow. The $$$i$$$-th line contains two integers $$$u_i$$$ and $$$v_i$$$ ($$$1 \le u_i,v_i \le n$$$, $$$u_i \ne v_i$$$) denoting that the $$$i$$$-th edge goes between vertices $$$u_i$$$ and $$$v_i$$$. The input is guaranteed to have no multiple edges or self loops. The graph is also guaranteed to be connected.

It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$10^6$$$. It is guaranteed that the sum of $$$m$$$ over all test cases does not exceed $$$2 \cdot 10^6$$$.

Output:

For each test case, output a binary string of length $$$m$$$. The $$$i$$$-th character of the string should be 1 if the $$$i$$$-th edge should be colored red, and 0 if it should be colored blue. If there are multiple ways to assign colors to edges that give the minimum answer, you may output any.

Sample Input:

4
5 7
1 2
2 3
3 4
4 5
5 1
1 3
3 5
4 4
1 2
2 3
1 4
3 4
6 7
1 2
1 3
3 4
4 5
1 4
5 6
6 2
2 1
1 2

Sample Output:

0111010
1001
0001111
0

Note:

• The corresponding graph of the first test case is:

  $$$c_1 + c_2 = 1 + 2 = 3$$$

• The corresponding graph of the second test case is:

  $$$c_1 + c_2 = 2 + 2 = 4$$$