BITMAP  Bitmap
There is given a rectangular bitmap of size n*m. Each pixel of the bitmap is either white or black, but at least one is white. The pixel in ith line and jth column is called the pixel (i,j). The distance between two pixels p_{1}=(i_{1},j_{1}) and p_{2}=(i_{2},j_{2}) is defined as:
Task
Write a program which:
 reads the description of the bitmap from the standard input,
 for each pixel, computes the distance to the nearest white pixel,
 writes the results to the standard output.
Input
The number of test cases t is in the first line of input, then t test cases follow separated by an empty line. In the first line of each test case there is a pair of integer numbers n, m separated by a single space, 1<=n <=182, 1<=m<=182. In each of the following n lines of the test case exactly one zeroone word of length m, the description of one line of the bitmap, is written. On the jth position in the line (i+1), 1 <= i <= n, 1 <= j <= m, is '1' if, and only if the pixel (i,j) is white.
Output
In the ith line for each test case, 1<=i<=n, there should be written m integers f(i,1),...,f(i,m) separated by single spaces, where f(i,j) is the distance from the pixel (i,j) to the nearest white pixel.
Example
Sample input: 1 3 4 0001 0011 0110 Sample output: 3 2 1 0 2 1 0 0 1 0 0 1
hide comments
ganpya:
20150813 06:49:57
BFS on whilte Pixel vs BFS on Black Pixel : AC vs TLE 

ALi Ibrahim:
20150803 00:13:50
easy problem, simple bfs, First Accepted in 0.24 :) 

monkz:
20150731 17:56:57
will O(n^3) solution work??


Vikrant Singh:
20150726 18:19:57
@Ashish


Ashish:
20150708 15:21:58
Can be done by simple brute force! I will try doing it by BFS though. 

shravinson:
20150708 13:38:40
it is giving WA


satyam0542:
20150705 11:43:21
make sure you are taking input of white and black spaces as a character..it costed me 3 wa. 

tropicalsurf:
20150627 16:11:05
The input specification is ambiguous: "t test cases follow separated by an empty line"


Mayank Jethva:
20150616 16:37:22
Good concept recognition question 

SangKuan:
20150616 09:02:58
use bfs.and be care of the index of array Last edit: 20150616 10:11:48 
Added by:  Piotr Ćowiec 
Date:  20040913 
Time limit:  4s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  6th Polish Olympiad in Informatics, stage 2 