Submit | All submissions | Best solutions | Back to list |
FFIRE - Forest Fires |
Forest fires are really dangerous, and can be started by even the smallest flame. Spreading from tree to tree, fires can engulf an entire forest in a matter of weeks. Given a map of a forest with locations of where a fire (or multiple fires) might have started, determine how long it would take the fire to capture the entire forest.
Input
The input contains a 10×10 map (i.e. 10 lines each consisting of 10 characters), where each character in the map is one of the following:
- . - blank space.
- T - a tree.
- F - a tree on fire.
Fires only spread from trees that are on fire to adjacent trees in one of four directions: North, South, East or West (so not diagonally). It takes 1 unit of time for the fire to spread from one location to the next. The fire spreads in all 4 directions at the same time (i.e. fires move outwards from the source).
Output
The output should contain the time it takes for the fire to capture the entire forest (i.e. the time it takes for every tree to catch fire). If some piece of the forest survives, output -1.
Example
Input: .......... .......... .......... .......... ..TTTTT... ..F...F... .......... .......... .......... .......... Output: 3
Added by: | Amlesh Jayakumar |
Date: | 2012-06-18 |
Time limit: | 1s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | All except: ASM64 |
Resource: | DWITE Programming Contest 2010 |
hide comments
|
|||||
2012-06-22 23:32:00 :D
With 10x10 some sub-optimal solutions, like O((W*H)^2), will pass. So increasing limit to something like 200x200 makes sense. |
|||||
2012-06-22 20:50:31 Amlesh Jayakumar
@Miguel- It isn't meant to be a challenging problem (though I do agree that increasing the size doesn't change the difficulty much). |
|||||
2012-06-22 13:47:25 Miguel Oliveira
Why limit the problem to just 10x10 maps? |