USACO 2015 US Open, Gold Problem 1. Googol
原题下载 USACO2015OPEN-G1 答案 (Analysis by Steven Hao) We first present a naive algorithm that recursively iterates through all nodes. Below is Python code implementing this naive algorithm, which...
USACO 2015 US Open, Silver Problem 3. Bessie's Birthday Buffet
原题下载 USACO2015OPEN-S3 答案 (Analysis by Nick Wu) Start by sorting the patches of the grass in increasing order of quality. Let f(i) be the maximum energy that we can accumulate if we end at pat...
USACO 2015 US Open, Silver Problem 2. Trapped in the Haybales (Silver)
原题下载 USACO2015OPEN-S2 答案 (Analysis by Nick Wu). If we pick a bale that we want to add hay to, then we can guarantee that Bessie cannot break through that bale. Therefore, once we have picked ...
USACO 2015 US Open, Silver Problem 1. Bessie Goes Moo
原题下载 USACO2015OPEN-S1 答案 (Analysis by Nick Wu) There are 5007 different combinations to check, which is far too many. However, just like with the bronze version of this problem, where we were...
USACO 2015 US Open, Bronze Problem 4. Palindromic Paths (Bronze)
原题下载 USACO2015OPEN-B4 答案 (Analysis by Nick Wu) Our first thought is to try all possible paths that Bessie can take. For small N, this works out well, but it turns out that for a grid of size ...
USACO 2015 US Open, Bronze Problem 2. Bessie Gets Even
原题下载 USACO2015OPEN-B2 答案 (Analysis by Nick Wu) In a pure brute-force solution, we would try every possible combination of assignments of variables to values. There are 7 variables, with at mo...
USACO 2015 US Open, Bronze Problem 3. Trapped in the Haybales (Bronze)
原题下载 USACO2015OPEN-B3 答案 (Analysis by Nick Wu) The NN hay bales define N−1N−1 intervals that Bessie can be inside. Let's consider answering for a given interval, whether Bessie can escape if ...
USACO 2015 US Open, Bronze Problem 1. Moocryption
原题下载 USACO2015OPEN-B1 答案 (Analysis by Nick Wu) There are too many substitution ciphers for us to check every single one and see which one gives the maximum number of MOOs. However, if we only...
USACO 2015 February Contest, Gold Problem 3. Fencing the Herd
原题下载 USACO2015FEB-G3 答案 (Analysis by Richard Peng) This problem is a dynamic (insertion of points) version of "a highway and seven dwarfs" from CEOI 2002. It asks to support a point set (the ...
