Exact Cover
- To: mathgroup at smc.vnet.net
 - Subject: [mg88312] Exact Cover
 - From: Johum <tuyenthanh101107 at yahoo.com>
 - Date: Thu, 1 May 2008 03:22:12 -0400 (EDT)
 
Hello All,
Someone can help me with this function?
ExactCover[matrix] 
finds all subsets of rows of the rectangular matrix which have exactly one nonzero element in each column.
   
   
matr = {{0, 0, 1, 0, 1, 1, 0}, 
        {1, 0, 0, 1, 0, 0, 1}, 
        {0, 1, 1, 0, 0, 1, 0},     
        {1, 0, 0, 1, 0, 0, 0}, 
        {0, 1, 0, 0, 0, 0, 1}, 
        {0, 0, 0, 1, 1, 0, 1}}
ExactCover[matr]
{{{1, 4}, {3, 5, 6}, {2, 7}}} 
Thanks All
Johum,