NQUEEN  Yet Another NQueen Problem
After solving Solution to the n Queens Puzzle by constructing, LoadingTime wants to solve a harder version of the NQueen Problem. Some queens have been set on particular locations on the board in this problem. Can you help him??
Input
The input contains multiple test cases. Every line begins with an integer N (N<=50), then N integers followed, representing the column number of the queen in each rows. If the number is 0, it means no queen has been set on this row. You can assume there is at least one solution.
Output
For each test case, print a line consists of N numbers separated by spaces, representing the column number of the queen in each row. If there are more than one answer, print any one of them.
Example
Input: 4 0 0 0 0 8 2 0 0 0 4 0 0 0 Output: 2 4 1 3 2 6 1 7 4 8 3 5
hide comments
nightwolf_9197:
20170402 15:54:17
how to avoid TLE ? what is expected time complexity. 

adichd123:
20160730 08:29:22
how to avoid tle??? 

Rishit Sanmukhani:
20150708 12:46:57
Really good problem. Can be solved by converting to exact cover problem. 

Gavin Liu:
20150128 03:09:02
the time limit maybe too strict for python 

zhangyw:
20120129 09:29:27
Just cover n columns... Last edit: 20120129 09:31:26 

Prabhat Chaudhary:
20110717 03:57:08
when do we consider that the input has terminated?? 

cherudim:
20110717 03:57:08
It drives me cracy


DAGA PIYUSH:
20110717 03:57:08
What is the exit condition?

Added by:  Bin Jin 
Date:  20070906 
Time limit:  0.640s 
Source limit:  10000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: CPP 
Resource:  own problem 