This was my first programming contest. It started at 1AM my time,

so I was a bit tired, but it was fun nonetheless.

Here are 3 that I got WA on and my algorithm. If someone finds

a hole in my algorithm or has some tricky input, let me know.

World Cup Noise (Problem G):

This looks like a simple fibonacci problem. out[1] = 2, out[2] = 3, out[3] = 5, out[4] = 8. However, I tried this and got WA. What tricky input am i missing (statement says only positive integer input)?

The Marriage Interview (Problem C)

Here are the outputs my program generates. What tricky input am I missing, or which of these are wrong.

Input:

Output:-1 3 0 3 1 3 2 3 3 3 4 3 5 3

0 1 1 1 2 1 3 1 4 1

0 0 1 0 2 0

61 61

Case 1: 1

Case 2: 1

Case 3: 1

Case 4: 4

Case 5: 7

Case 6: 13

Case 7: 25

Case 8: 1

Case 9: 1

Case 10: 2

Case 11: 3

Case 12: 4

Case 13: 1

Case 14: 1

Case 15: 1

Make Polygon (B)

Root of problem was to figure out whether angles were interior angles or exterior angles (where you have to do angle = 360 - angle).

I used the sum of (x

*y[i+1]-x[i+1]y*

*) to determine whether the polygon was clockwise or counterclockwise. I then used this along with the sign of the cross product to see whether I had an interior angle or exterior angle. I tried some pretty simple inputs:*

3

0 0 10 0 5 10

3

0 0 5 10 10 0

5

0 0 5 5 10 0 10 10 0 10

5

0 0 0 10 10 10 10 0 5 5

Were there other tricks (self intersecting polygons, etc.)? Are my equations above totally hosed for non-convex polygons?3

0 0 10 0 5 10

3

0 0 5 10 10 0

5

0 0 5 5 10 0 10 10 0 10

5

0 0 0 10 10 10 10 0 5 5

Were there other tricks (self intersecting polygons, etc.)? Are my equations above totally hosed for non-convex polygons?