ASSASSIN - Assassin Creed

Ezio needs to kill N targets located in N different cities. The cities are connected by some one way roads. As time is short, Ezio can send a massage along with the map to the assassin's bureau to send some assassins who will start visiting cities and killing the targets. An assassin can start from any city, he may visit any city multiple times even the cities that are already visited by other assassins. Now Ezio wants to find the minimum number of assassins needed to kill all the targets.

Input

Input starts with an integer T (≤ 70), denoting the number of test cases.

Each case starts with a blank line. Next line contains two integers N (1 ≤ N ≤ 1000) and M (0 ≤ M ≤ 10000), where N denotes the number of cities and M denotes the number of one way roads. Each of the next M lines contains two integers u v (1 ≤ u, v ≤ N, u ≠ v) meaning that there is a road from u to v. Assume that there can be at most one road from a city u to v.

Output

For each case, print the case number and the minimum number of assassins needed to kill all targets.

Sample Input

Output for Sample Input

3

 

5 4

1 2

1 3

4 1

5 1

 

7 0

 

8 8

1 2

2 3

3 4

4 1

1 6

6 7

7 8

8 6

Case 1: 2

Case 2: 7

Case 3: 2

Note

Dataset is huge, use faster I/O methods.


Được gửi lên bởi:Race with time
Ngày:2012-11-06
Thời gian chạy:1s-2s
Giới hạn mã nguồn:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Ngôn ngữ cho phép:Tất cả ngoại trừ: ASM64 GOSU PERL6 PYPY RUST SED

hide comments
2016-12-24 20:59:56
SCC + Path Cover
2016-09-24 15:50:32
code:
http://shink.in/wxiUV
2015-03-05 15:27:11 Duc M. Pham
Edited

Last edit: 2015-03-05 16:04:48
2014-11-26 15:33:20 livw
đề này của tàu khựa
2012-11-07 13:06:31 Race with time
Em bị TLE
2012-11-07 09:27:14 con_nha_ngheo
Ps xem hộ em xem em bị TLE hay là WA, em đc. 97.22
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