ASSIGN - Assignments

Problem

Your task will be to calculate number of different assignments of n different topics to n students such that everybody gets exactly one topic he likes.

Input

First line of input contains number of test cases c (1<=c<=80). Each test case begins with number of students n (1<=n<=20). Each of the next n lines contains n integers describing preferences of one student. 1 at the ith position means that this student likes ith topic, 0 means that he definitely doesn't want to take it.

Output

For each test case output number of different assignments (it will fit in a signed 64-bit integer).

Example

Input:
3
3
1 1 1
1 1 1
1 1 1
11
1 0 0 1 0 0 0 0 0 1 1 
1 1 1 1 1 0 1 0 1 0 0 
1 0 0 1 0 0 1 1 0 1 0 
1 0 1 1 1 0 1 1 0 1 1 
0 1 1 1 0 1 0 0 1 1 1 
1 1 1 0 0 1 0 0 0 0 0 
0 0 0 0 1 0 1 0 0 0 1 
1 0 1 1 0 0 0 0 0 0 1 
0 0 1 0 1 1 0 0 0 1 1 
1 1 1 0 0 0 1 0 1 0 1 
1 0 0 0 1 1 1 1 0 0 0 
11
0 1 1 1 0 1 0 0 0 1 0 
0 0 1 1 1 1 1 1 1 1 1 
1 1 0 1 0 0 0 0 0 1 0 
0 1 0 1 0 1 0 1 0 1 1 
1 0 0 1 0 0 0 0 1 0 1 
0 0 1 0 1 1 0 0 0 0 1 
1 0 1 0 1 1 1 0 1 1 0 
1 0 1 1 0 1 1 0 0 1 0 
0 0 1 1 0 1 1 1 1 1 1 
0 1 0 0 0 0 0 0 0 1 1 
0 1 1 0 0 0 0 0 1 0 1 

Output:
6
7588
7426


Added by:gawry
Date:2005-10-08
Time limit:2.997s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: NODEJS PERL6 VB.NET

hide comments
2017-02-24 03:30:41
Wow, AC and #2 time on 1st try :-D
Bit operations galore and O(2^N * N), as opposed to O(2^N * N^2).
A bit of combinatorics and common sense help a lot in making that solution faster; so does __builtin_popcount.

Last edit: 2017-02-24 03:35:22
2017-02-02 23:26:11
to count no of 1s in mask use __builtin_popcount(mask);
2017-01-18 06:33:35
how people are solving it in 0.15 sec... mine solution dp(top down) took 2.5 secs.... is there any better and optimal method to solve??????/
2016-11-07 21:31:07
Topdown+bitmasking :-D
2016-10-15 08:20:36
My O(2^n*n) Gets tle Xp for each case lol
2016-10-10 16:49:52 dev
Very Nice DP + BitMasking !
O(2^n * n*n ) will give Tle.
2016-09-22 15:12:53
learned new things :'D
2016-09-21 11:52:19 srinath
Using map gives TLE. Use vector instead.
2016-07-27 15:32:52
@vikikkdi : seri
2016-06-25 06:16:14
can anyone explain me the test cases??
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