Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises)
5 problems from Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) (contest 1039), difficulty 2100-3400. 3/5 solutions verified against sample I/O.
Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises)
Div. 1 | 5 problems | 3/5 verified | Difficulty 2100-3400 | 34m 14s
| # | Problem | Rating | Tags | Accepted | Time | ✓ |
|---|---|---|---|---|---|---|
| A | Timetable | 2300 | constructive-algorithms, data-structures, greedy | 861 | 6m 10s | |
| B | Subway Pursuit | 2100 | binary-search, interactive, probabilities | 2,589 | 11m 23s | |
| C | Network Safety | 2200 | dfs-and-similar, dsu, graphs | 1,490 | 8m 24s | ✓ |
| D | You Are Given a Tree | 2800 | data-structures, dp, trees | 2,308 | 3m 5s | ✓ |
| E | Summer Oenothera Exhibition | 3400 | data-structures | 319 | 5m 12s | ✓ |
CF 1039E - Summer Oenothera Exhibition
We are given a sequence of photo intervals on a very large number line. Each photo covers a fixed window of length w, starting at position xi, so photo i covers [xi, xi + w - 1].
CF 1039B - Subway Pursuit
We are dealing with a single moving target on a very large numbered line of stations from 1 to n. At any moment there is exactly one station where the train is located, but after every query the train is allowed to move up to k stations left or right, and this movement is…
CF 1039D - You Are Given a Tree
We are working with a tree where we want to select several simple paths, with a strict rule that no vertex can belong to more than one selected path.
CF 1039C - Network Safety
We are given a network of servers where each server has an integer label (an encryption key) in a fixed bit range. Some pairs of servers are connected, and a connection is considered safe only if the two endpoints currently hold different values.
CF 1039A - Timetable
We are given a fixed sequence of departure times from station A, strictly increasing, and for each bus we also know a constraint on how “late” it can possibly appear in the arrival order at station B.