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
2019-05-27 14:23:27
First time got TLE after using recursive 2d memorization DP, next I used 1d DP and got accepted, really a very nice problem for learning bitmasking with DP.
2019-03-28 12:49:02
NOBODY LOVES THE ASSIGNMENTS
THINK OF 1-D DP
HINT -NO OF PEOPLES HAS ASSIGNED ARE=NO OF SET BITS INT MASK
2019-03-16 19:26:42
Top-down DP works. Finally got AC after many TLEs. Hint: 1D memoization works.
2018-10-11 13:41:50
Learn Bitmask DP first.. Use mask to keep track which books have been taken so far.
2018-09-11 01:31:04
for those who solve the problem and come to show off in comments.. "fuck you"
2018-08-19 03:56:20
After this, try: https://www.codechef.com/AUG14/problems/TSHIRTS

Last edit: 2018-08-19 03:59:23
2018-06-29 09:50:51
bitset tle:bitmask ac
2018-06-14 22:22:48
question is quite easy
DP + bitmasking
use long long
for each test case dont clear complete dp table (I got 2 TLE)
10^8 memory can be used
2018-06-11 13:12:12
My first dp+bitmasking learnt a lot
2018-05-16 17:12:44
My first dp+bitmasking !! Very nice. Learnt alot
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