Ri, Ju Song

• Username: 6★pustcsrjs2021
• Country:  North Korea
• Student/Professional:Student
• Institution:Pyongyang University of Science and Technology North Korea
• CodeChef Pro Plan: No Active Plan. View Details

Submissions Heat Map

Last 6 Months 2025 (Jul-Dec)2025 (Jan-Jun)2024 (Jul-Dec)2024 (Jan-Jun)

Rating Graph

No. of Contests Participated: 6

Current Ratings Graph Old Ratings Graph

2212 (+26)RatingProvisional
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September Lunchtime 2021 Division 1(2021-09-25 21:30:00)

Global Rank:   69

Cheated in:   

Ratings System Update

(2021-09-25 21:30:00)

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2212 (-27)RatingProvisional
Rating i Provisional Rating, click to know more

September Lunchtime 2021 Division 1(2022-12-20 00:00:00)

Global Rank:   69

Cheated in:   

Ratings System Update

(2022-12-20 00:00:00)

This is the difference due to changing the rating system.This graph is not updated after 20th Dec 2022. Know more

How the rating system works?

Learning Paths (0)

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Practice Paths (0)

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Contests (6)

July Cook-Off 2021 Division 3

Mod Equality, Shoe Fit, Hidden Colored Graph, XOR-ORED

July Lunchtime 2021 Division 2

Beautiful Pairs, Array Rotation Returns

August Challenge 2021 Division 2 (Unrated)

Fat Hut, Olympics Ranking, Problem Difficulties, Chef and Digits of Large Numbers, Charge Scheduling, Alternating LG Queries, Chef and Bulb Invention, Geometry 1, Array Filling, Special Triplets

August Cook-Off 2021 Division 2

Odd Array, Different String, Chef and Closure, Equal Difference, Interactive Equivalency, Clear the Array

August Lunchtime 2021 Division 1

Just a Graph

September Challenge 2021 Division 1 (Unrated)

Travel Pass, Minimum Digit Sum 2, Covaxin vs Covishield, Airline Restrictions, Treasure Hunt, Minimize Digit Sum, Shuffling Parities, XOR Equal, 2-D Point Meeting

September Cook-Off 2021 Division 1

Chess Kings Chasing Game, Chef and Pairwise Distances, Fake Swaps

October Challenge 2021 Division 1 (Unrated)

Chef at the Olympics, Longest AND Subarray, Digit Removal, MEX-OR, Yet another MEX problem, Characteristic Polynomial Verification, Hidden Points

September Lunchtime 2021 Division 1

Alice vs Bob Faceoff, Interesting Representation

November Challenge 2021 Division 1 (Unrated)

Flip or Compress, Functional Array, Wildcard Replacement, Xor Equation, Weird Palindrome Making, Hill Sequence, Maximise the bridges, Convex Hulk

December Challenge 2021 Division 1 (Unrated)

Increasing String , Yet Another Tree Problem, Valleys and Hills, Rock Paper Scissors, Pyramid Traversal, Min Manhattan Distance, Squares Counting

Total Problems Solved: 170