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这不是作业问题，而是我想知道这是否是学习编程所需要的。我一直登录 TopCoder 并不是为了实际参与，而是为了基本了解问题是如何解决的。但据我所知，我不明白问题是什么以及如何将问题转化为可以解决它的算法。
刚才正好看到了正在中国举行的ACM ICPC 2010 全局总决赛。团队得到了问题集，其中之一是:
Given at most 100 points on a plan with distinct x-coordinates,
find the shortest cycle that passes through each point exactly once,
goes from the leftmost point always to the right until it reaches the
rightmost point, then goes always to the left until it gets back to the
leftmost point. Additionally, two points are given such that the the path
from left to right contains the first point, and the path from right to
left contains the second point. This seems to be a very simple DP: after
processing the last k points, and with the first path ending in point a
and the second path ending in point b, what is the smallest total length
to achieve that? This is O(n^2) states, transitions in O(n). We deal
with the two special points by forcing the first path to contain the first
one, and the second path contain the second one.
现在我不知道在阅读问题集后应该解决什么问题。
还有一个来自 google code jam:
Problem
In a big, square room there are two point light sources:
one is red and the other is green. There are also n circular pillars.
Light travels in straight lines and is absorbed by walls and pillars.
The pillars therefore cast shadows: they do not let light through.
There are places in the room where no light reaches (black), where only
one of the two light sources reaches (red or green), and places where
both lights reach (yellow). Compute the total area of each of the four
colors in the room. Do not include the area of the pillars.
Input
* One line containing the number of test cases, T.
Each test case contains, in order:
* One line containing the coordinates x, y of the red light source.
* One line containing the coordinates x, y of the green light source.
* One line containing the number of pillars n.
* n lines describing the pillars. Each contains 3 numbers x, y, r.
The pillar is a disk with the center (x, y) and radius r.
The room is the square described by 0 ≤ x, y ≤ 100. Pillars, room
walls and light sources are all disjoint, they do not overlap or touch.
Output
For each test case, output:
Case #X:
black area
red area
green area
yellow area
是否要求编程人员应该能够解决这类问题？
如果有人能帮助我解释 google code jam 问题集，我将不胜感激，因为我希望参加今年的 Code Jam，看看我是否能做些什么。
谢谢。