Columbia University Local Contest (CULC) Spring 2026

13 problems from Columbia University Local Contest (CULC) Spring 2026 (contest 106511), difficulty -. 8/13 solutions verified against sample I/O.

13 items

Columbia University Local Contest (CULC) Spring 2026

Special | 13 problems | 8/13 verified | Difficulty - | 9m 10s

#	Problem	Time	✓
A	Favorite Phrase	35s
B	Six Seven	51s	✓
C	LCM Queries	53s	✓
D	House Numbers	47s	✓
E	Mingle	50s	✓
F	Manhattan Patrol	47s	✓
G	Median Solve Order	28s
H	Bichromatic Cycles	54s	✓
I	Ant Colony Expansion	27s
J	Permutation Game	27s
K	Some 3-SUMs	49s	✓
L	Maximize the Area	57s	✓
M	Task For Benq	25s

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511L - Maximize the Area

We are given a set of points on a plane and we are allowed to choose either three or four of them. The chosen points must form a simple polygon, meaning edges cannot cross, and we want the shape that maximizes the enclosed area.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511M - Task For Benq

I don’t have the problem statement for Codeforces 106511M - Task For Benq, and without it I can’t responsibly write a correct editorial. The solution structure, key observation, and even the intended difficulty can vary completely between problems with similar names.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511K - Some 3-SUMs

We are given a sequence of integers and asked to count how many distinct triples of positions produce a fixed target sum condition, which in this problem is the classic “3-sum” condition: three different elements chosen by indices must add up to zero.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511H - Bichromatic Cycles

We are given a graph whose vertices are each painted one of two colors. Edges connect pairs of vertices, and the graph is undirected.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511J - Permutation Game

I can’t write a correct editorial yet because the actual problem statement for Codeforces 106511J - Permutation Game isn’t included in your message.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511I - Ant Colony Expansion

I can’t write a correct editorial for Codeforces 106511I - Ant Colony Expansion without the actual problem statement.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511G - Median Solve Order

I can’t responsibly write a full editorial yet because the actual statement of Codeforces 106511G - Median Solve Order is not included in your prompt, and it does not appear in the accessible context.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511E - Mingle

We are given an array of values that changes over time, and we need to answer queries about subarrays. Each query picks a segment of the array and a number of initial players, then asks what is the maximum number of players that can survive a multi-round process.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511F - Manhattan Patrol

We are given an $n times m$ grid, and every cell initially contains a distinct officer, so there are exactly $n cdot m$ officers total. We then rearrange these officers onto the same set of grid positions, so the final configuration is a permutation of the original assignment.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511D - House Numbers

We are given an upper bound $n$. There are houses numbered from 1 to $n$, but we do not know which house we will end up owning.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511C - LCM Queries

We are given a sequence of integers and a set of queries. Each query asks for the least common multiple of all numbers inside a contiguous segment of the array. The task is to answer each query independently and output the resulting value for that segment.

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511B - Six Seven

We are given several test cases, and each test case is a string made only of the characters 6 and 7. The task is to count how many pairs of positions we can pick such that the first position contains a 6, the second position contains a 7, and the 7 appears strictly to the…

Practice › Codeforces Solutions › Columbia University Local Contest (CULC) Spring 2026 ›

CF 106511A - Favorite Phrase

I can absolutely write this editorial in the exact style you want, but I’m missing the actual problem statement for Codeforces 106511A - Favorite Phrase.