In the map of London Tower shown below, five guards are represented
by the letters A, B, C, D, and E (in the grid).   Promptly at the firing of a gun,
which denotes the setting of the sun and the changing of the guard,
guard A marches out by exit a, B exits at b, C exits at c, D exits at d,
and guard E marches from his present cell to cell F.

The problem is to discover how the five guards can make these five marches
without any one guard crossing the line of march of another.   In other words,
no more than one line of march is permitted through any one cell.



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Solution to the Problem:



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Correctly solved by:

1. James Alarie Flint, Michigan
2. Britan Woody Mountain View High School,
Mountain View, Wyoming
3. Alyx Wells Mountain View High School,
Mountain View, Wyoming
4. SreeRoopa Sankararaman Singapore
5. Behlee Aimone Mountain View High School,
Mountain View, Wyoming
6. Linzy Carpenter Mountain View High School,
Mountain View, Wyoming
7. Lakota Dulce Mountain View High School,
Mountain View, Wyoming
8. Mckinzee Walker Mountain View High School,
Mountain View, Wyoming
9. Dawson Case Mountain View High School,
Mountain View, Wyoming
10. Mashayla Hurdsman Mountain View High School,
Mountain View, Wyoming
11. Madison Bindl Mountain View High School,
Mountain View, Wyoming
12. Dallie Hewitt Mountain View High School,
Mountain View, Wyoming
12. Morganne Johnson Mountain View High School,
Mountain View, Wyoming
13. Chase Smith Mountain View High School,
Mountain View, Wyoming
14. Christopher Woody Mountain View High School,
Mountain View, Wyoming
15. Eliza Sheffield and Anna Tetzlaff Tuscaloosa, Alabama
16. Hope Pfeifer Mountain View High School,
Mountain View, Wyoming
17. Faith Pfeifer Mountain View High School,
Mountain View, Wyoming
18. Hunter Gross Mountain View High School,
Mountain View, Wyoming