题目描述
There is a city with $N$ numbered $0 - N-1$ shops. A market is a place where we can reach from one shop to another using some road. There are $M$ roads in this city connecting each connecting any two shops.
Find the number of markets in the city.
NOTE: A market having only one shop is also a valid market.
-----Input:-----
- First line will contain $T$, number of testcases. Then the testcases follow.
- First line of Each Test Case is $N, M$, denoting the number of shops and the number of roads respectively.
- Next M lines consist of two integers $A$ and $B$ denoting that there exists a road between Shop A and Shop B
-----Output:-----
For each testcase, output the number of markets.
-----Constraints-----
- $1 \leq T \leq 100$
- $1 \leq N,M \leq 10^3$
- $0 \leq A,B < N$
-----Sample Input:-----
1
5 3
0 1
2 3
3 4
-----Sample Output:-----
2
输入格式
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输出格式
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