2020 China Collegiate Programming Contest Qinhuangdao Site

11 problems from 2020 China Collegiate Programming Contest Qinhuangdao Site (contest 102769), difficulty -. 8/11 solutions verified against sample I/O.

11 items

2020 China Collegiate Programming Contest Qinhuangdao Site

Special | 11 problems | 8/11 verified | Difficulty - | 14m 30s

# Problem Rating Tags Accepted Time ✓
A A Greeting from Qinhuangdao 1m 1s ✓
B Bounding Wall 1m 47s ✓
D Defend City 1m 36s ✓
E Exam Results 58s
F Friendly Group 56s ✓
G Good Number 1m 9s ✓
H Holy Sequence 1m 25s
I Interstellar Hunter 1m 18s ✓
J Jewel Splitting 1m 8s ✓
K Kingdom's Power 1m 22s ✓
L Lost Temple 1m 50s
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769B - Bounding Wall

We have a rectangular map of cells. A dry cell is represented by and a wet cell is represented by .. A bounding wall is the border of a rectangle, but the problem asks for its covered rectangle area.
codeforces competitive-programming Jul 30, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769D - Defend City

The city is a square region from (0,0) to (n+1,n+1). Each defensive tower sits at an integer coordinate inside the square and protects one of the four quadrants extending from its position.
codeforces competitive-programming Jul 30, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769L - Lost Temple

I can write the editorial, but the problem statement section in your prompt is empty, so I do not have the exact rules, input format, and required output details needed to produce a correct algorithm and implementation.
codeforces competitive-programming Jul 30, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769H - Holy Sequence

I need the actual problem statement details to write a reliable editorial and solution. Which version of the problem statement should I use? Waiting for your answer
codeforces competitive-programming Jul 30, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769E - Exam Results

I can write the editorial, but I need the actual statement details for Codeforces 102769E - Exam Results. The problem statement section in your prompt is empty, and the available references only expose partial solution code, not the full description of what the variables a, b…
codeforces competitive-programming Jul 30, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769A - A Greeting from Qinhuangdao

The problem describes a collection of red and blue balls. There are r red balls and b blue balls, and two balls are selected uniformly at random without replacement.
codeforces competitive-programming Jul 30, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769K - Kingdom's Power

The world is a rooted tree with kingdom 1 as the capital. Every kingdom except the capital has exactly one parent, and the input gives these parent relationships. Alex owns unlimited armies, but only one army can be ordered to move by one edge during each week.
codeforces competitive-programming Jul 29, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769J - Jewel Splitting

The jewelry is a string of gemstones, where each character represents one type of gemstone. For a chosen width d, the string is cut from left to right into several complete pieces of length d. The incomplete suffix, if it exists, is discarded.
codeforces competitive-programming Jul 28, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769I - Interstellar Hunter

The problem models a spaceship that starts at the origin of an infinite grid. During the game, new jump skills are added.
codeforces competitive-programming Jul 28, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769G - Good Number

A direct solution would iterate over every integer x from 1 to n. For each number, we would compute a = floor(x^(1/k)) and test whether x % a == 0. This is correct because it follows the definition exactly.
codeforces competitive-programming Jul 28, 2026
Practice › Codeforces Solutions › 2020 China Collegiate Programming Contest Qinhuangdao Site ›

CF 102769F - Friendly Group

The problem describes a friendship graph. Each student is a vertex, and every friendship relation is an undirected edge. We must choose any subset of students to form a group.
codeforces competitive-programming Jul 28, 2026