DWITE Online Computer Programming Contest
January 2008
Problem 4
Shortest path around
Sometimes an open field could be as much of a maze as narrow tunnels. Given an obstacle in an otherwise empty room, what is the shortest path around it?
The input file DATA4.txt will contain five sets of data, each a 10 by 10 character matrix. There will be a line of 10 dashes after each set, to visually delimit sets of data. The character representations are as follows:
- . - empty space
- # - wall
- X - one of the ends
The output file OUT4.txt will contain five lines -- each an integer distance between the two points marked with X.
There will always be only two X spots per set. There will always be a valid path. Valid steps are into any adjacent empty space; diagonal steps are legal. Refer to sample data for examples.
Sample Input (only first two sets given):
.......... .......... .......... ....#..... ....#..... X...#...X. ....#..... ....#..... .......... .......... ---------- .......... .......... ........#. ........#. X...#####X ...#...... ..#....... .......... .......... .......... ----------
Sample Output (only first two sets given):
8 9