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#1881. [Seerc2008]Lucky cities

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Description

给出一张N个点M条边的无向简单图,其中N≤100000,M≤100000。定义一个有效的“行程”为一个点数为奇数的简单圈,即所有点在圈上只能出现一次。如果一个点至少处于一个“行程”中,那么它被称为“幸运的”,要求求出图中幸运点的数目。

Input

The first line of input contains a single integer T – a number of test cases. Every test case starts with a line containing two integers separated by a single space – N and M. Each of the next M lines will contain two integers ai and bi separated by a single space – the labels of cities that i-th road connects.

Output

Output should contain T lines – answers for each of the test cases.

Sample Input

1 ≤ T ≤ 77,
0 ≤ N, M ≤ 100000 (105
),
1 ≤ ai < bi ≤ N.

Sample Output

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

Hint

3

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