Educational Codeforces Round 169 (Rated for Div. 2)

Solutions for Educational Codeforces Round 169 (Rated for Div. 2) (contest 2004). 3/7 problems verified against sample I/O. Difficulty range: 800-3200.

7 items

Educational Codeforces Round 169 (Rated for Div. 2)

Type: Div. 2 | Problems: 7 | Verified: 3/7 | Rating range: 800-3200 | Time: 18m 35s

Problem Name Rating Tags Solve Time Verified
A Closest Point 800 implementation, math 1m 10s ✓
B Game with Doors 1000 brute-force, greedy 5m 23s ✗
C Splitting Items 1100 games, greedy, sortings 6m 31s ✗
D Colored Portals 1600 binary-search, brute-force, data-structures 1m 42s ✓
E Not a Nim Problem - - - ✗
F Make a Palindrome 2600 binary-search, brute-force, data-structures 2m 39s ✗
G Substring Compression 3200 data-structures, dp, matrices 1m 10s ✓
Practice › Codeforces Solutions › Educational Codeforces Round 169 (Rated for Div. 2) ›

Practice › Codeforces Solutions › Educational Codeforces Round 169 (Rated for Div. 2) ›

CF 2004B - Game with Doors

We are given a one-dimensional line of 100 rooms, connected consecutively by 99 doors. Each door can either be open or locked, and movement is only possible through open doors between adjacent rooms.
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CF 2004C - Splitting Items

We are given a list of items with integer costs, and two players, Alice and Bob, take turns picking items starting with Alice. After all items are taken, the score is the total cost Alice collected minus the total cost Bob collected.
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Practice › Codeforces Solutions › Educational Codeforces Round 169 (Rated for Div. 2) ›

CF 2004G - Substring Compression

We are given a digit string. For every substring of length exactly k, we must compute the minimum possible length after performing one compression operation.
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CF 2004F - Make a Palindrome

Working
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CF 2004A - Closest Point

We are given a set of integer points on a one-dimensional line. The distance between two points is their absolute difference.
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CF 2004D - Colored Portals

We are given a sequence of cities arranged on a line, each equipped with exactly two portals of different colors from a fixed set of four: blue, green, red, and yellow.
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