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USACO 2017 US Open Bronze Problem 3 Modern Art Problem Link

I am once again trying to solve a problem to practice for the upcoming USACO contest, and am having trouble meeting the time limit of 1 second: https://open.kattis.com/contests/v4xrif/problems/knigsoftheforest

All moose are knigs of the forest, but your latest moose-friend, Karl-Älgtav, is more interesting than most. In part because of his fondness of fermented blueberries, and in part because of the tribe he lives in. Each year his tribe holds a tournament to determine that year’s alpha-moose. The winner gets to lead the tribe for a year, and then permanently leaves the tribe. The pool of contenders stays constant over the years, apart from the old alpha-moose being replaced by a newcomer in each tournament.

Karl-Älgtav has recently begun to wonder when it will be his turn to win, and has asked you to help him determine this. He has supplied a list of the strength of each of the other moose in his tribe that will compete during the next n−1 years, along with their time of entry into the tournament. Assuming that the winner each year is the moose with greatest strength, determine when Karl-Älgtav becomes the alpha-moose.

Input The first line of input contains two space separated integers k (1≤k≤100000) and n (1≤n≤100000), denoting the size of the tournament pool and the number of years for which you have been supplied sufficient information.

Next is a single line describing Karl-Älgtav, containing the two integers y (2011≤y≤2011+n−1) and p (0≤p≤2^31−1). These are his year of entry into the tournament and his strength, respectively.

Then follow n+k−2 lines describing each of the other moose, in the same format as for Karl-Älgtav.

Note that exactly k of the moose will have 2011 as their year of entry, and that the remaining n−1 moose will have unique years of entry.

You may assume that the strength of each moose is unique.

Output The year Karl-Älgtav wins the tournament, or unknown if the given data is insufficient for determining this.

Sample Input 1

...

I am currently working on a USACO problem and I recently met a roadblock. My program can do what the question asks, just not in the specified time limit, which I think is around 4 seconds.

The problem is as follows:

Bessie is a busy computer science graduate student. However, even graduate students need friends. As a result, Farmer John has opened a pasture with the explicit purpose of helping Bessie and other cows form lasting friendships. Farmer John's pasture can be regarded as a large 2D grid of square "cells" (picture a huge chess board). Each cell is labeled with:

• 'C' if the cell contains a cow.
• 'G' if the cell contains grass.
• '.' if the cell contains neither a cow nor grass.

For two distinct cows to become friends, the cows must choose to meet at a grass-covered square that is directly horizontally or vertically adjacent to both of them. During the process, they eat the grass in the grass-covered square, so future pairs of cows cannot use that square as a meeting point. The same cow may become friends with more than one other cow, but no pair of cows may meet and become friends more than once.

Farmer John is hoping that numerous pairs of cows will meet and become friends over time. Please determine the maximum number of new friendships between distinct pairs of cows that can possibly be created by the end of this experience.

INPUT FORMAT (input arrives from the terminal / stdin): The first line contains N and M (N,M≤1000). The next N lines each contain a string of M characters, describing the pasture.

OUTPUT FORMAT (print output to the terminal / stdout): Count the maximum number of pairs of cows that can become friends by the end of the experience.

SAMPLE INPUT:

I am practicing for the upcoming USACO competition in December, and am attempting to solve this problem: http://www.usaco.org/index.php?page=viewproblem2&cpid=1131

Bessie the cow has enrolled in a computer science PhD program, driven by her love of computer science and also the allure of one day becoming "Dr. Bessie". Having worked for some time on her academic research, she has now published N papers (1≤N≤100000), and her i-th paper has accumulated ci citations (0≤ci≤100000) from other papers in the research literature. Bessie has heard that an academic's success can be measured by their h-index. The h-index is the largest number h such that the researcher has at least h papers each with at least h citations. For example, a researcher with 4 papers and respective citation counts (1,100,2,3) has an h-index of 2, whereas if the citation counts were (1,100,3,3) then the h-index would be 3.

To up her h-index, Bessie is planning to write a survey article citing several of her past papers. Due to page limits, she can include at most L citations in this survey (0≤L≤100000), and of course she can cite each of her papers at most once.

Help Bessie determine the maximum h-index she may achieve after writing this survey.

Note that Bessie's research advisor should probably inform her at some point that writing a survey solely to increase one's h index is ethically dubious; other academics are not recommended to follow Bessie's example here.

INPUT FORMAT (input arrives from the terminal / stdin):

The first line of input contains N and L. The second line contains N space-separated integers c1,…,cN.

OUTPUT FORMAT (print output to the terminal / stdout):

The maximum h-index Bessie may achieve after writing the survey.

SAMPLE INPUT:

I am currently trying to answer the USACO US Open 2020 bronze question 3 in python. (http://www.usaco.org/index.php?page=viewproblem2&cpid=1037)

I can get the correct output for all of the test cases, but I exceed the time limit for test case 13.

The time limit for each test case when you're using python is around 4 seconds, and I don't know how to speed up the code. Some advice would be great!

Test case 13:

As a competitive programmer, I've always used ios::sync_with_stdio(0); to speed up cin and cout. But I've also seen other people use optimizations like cin.sync_with_stdio(0); or cout.sync_with_stdio(0);. For example, the latter two were used in this website: https://usaco.guide/general/fast-io?lang=cpp.

I know that ios::sync_with_stdio(0); unsyncs iostream(cin and cout) from stdio(scanf and printf), so why would someone unsync only the input cin or only the output cout when doing competitive programming (which usually has a large amount of both input and output)?

I am practicing for USACO and I came across the "Censoring" Problem: http://www.usaco.org/index.php?page=viewproblem2&cpid=526

I solved it pretty quickly and though I got it right. However, it turns out that my the server gives me a time error for test cases 7-15 (it works well for the first 6 test cases).

Here is my code.

I'm getting this runtime error for the 2017 USACO Bronze question 1. I am using python to solve it. Runtime errors are pretty common for me and I really have a hard time fixing them. Can someone help me figure out which part of my code is bad. I am very new to competitive programming (in fact this is the first USACO question I have solved) so please bear with me. Here is the problem http://www.usaco.org/index.php?page=viewproblem2&cpid=759

I am currently trying to solve a simple version of checkers with python. Specifically, I am trying to solve the problem "checkers" from USACO 2008 December Bronze contest. (Problem Link)

My idea is to run a recursive dfs function on the location of each of the kings. However, I have encountered some issues with my dfs function. When I run my dfs function multiple times, the function produces different outputs, even with the same parameters. Specifically, it only produces the right outputs in the first time. I don't know what is happening, any help will be appreciated, thank you! (I am using Python 3.7)

Here is my dfs function: