Codeforces Global Round 6

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ContestId
Name
Phase
Frozen
Duration (Seconds)
Relative Time
Start Time
1266 Codeforces Global Round 6 FINISHED False 9000 160844087 Dec. 17, 2019, 3:05 p.m.

Problems

Solved$
Index
Name
Type
Tags
Community Tag
Rating
( 104 ) H Red-Blue Graph PROGRAMMING dp graphs math matrices meet-in-the-middle 3400

B"There is a directed graph on n vertices numbered 1 through n where each vertex (except n ) has two outgoing arcs, red and blue. At any point in time, exactly one of the arcs is active for each vertex. Initially, all blue arcs are active and there is a token located at vertex 1 . In one second, the vertex with token first switches its active arcs -- the inactive arc becomes active and vice versa. Then, the token is moved along the active arc. When the token reaches the vertex n , it stops. It is guaranteed that n is reachable via arcs from every vertex. You are given q queries. Each query contains a state of the graph -- a pair (v, s) of the following form: For each query, determine whether the given state is reachable from the initial state and the first time this configuration appears. Note that the two operations (change active arc and traverse it) are atomic -- a state is not considered reached if it appears after changing the active arc but before traversing it. The first line contains a single integer n ( 2 <= q n <= q 58 ) -- the number of vertices. n-1 lines follow, i -th of contains two space separated integers b_i and r_i ( 1 <= q b_i, r_i <= q n ) representing a blue arc (i, b_i) and red arc (i, r_i) , respectively. It is guaranteed that vertex n is reachable from every vertex. The next line contains a single integer q ( 1 <= q q <= q 5000 ) -- the number of queries. Then q lines with queries follow. The j -th of these lines contains an integer v ( 1 <= q v < n ) and a string s of length n-1 consiting only of characters 'R' and 'B'. The i -th of these characters is 'R' if the red arc going from i is active and 'B' otherwise. Output q lines, each containing answer to a single query. If the state in the i -th query is unreachable, output the integer -1 . Otherwise, out"...

Tutorials

Codeforces Global Round 6 Editorial

Submissions

Submission Id
Author(s)
Index
Submitted
Verdict
Language
Test Set
Tests Passed
Time taken (ms)
Memory Consumed (bytes)
Tags
Rating
68142693 yasugongshang H Jan. 4, 2020, 12:46 a.m. OK GNU C++11 TESTS 66 483 307200 3400
67320658 Rubblsh12345 H Dec. 21, 2019, 7:54 a.m. OK GNU C++11 TESTS 66 1638 102400 3400
67159845 NikTsDodik H Dec. 18, 2019, 1:37 p.m. OK GNU C++14 TESTS 64 93 204800 3400
67128836 Benq H Dec. 17, 2019, 9:45 p.m. OK GNU C++14 TESTS 64 468 307200 3400
67125982 ansa H Dec. 17, 2019, 8:08 p.m. OK GNU C++17 TESTS 64 62 204800 3400
69563075 gongsuidashen H Jan. 26, 2020, 11:22 a.m. OK GNU C++17 TESTS 66 264 307200 3400
69469698 Atoev__Urvatullo H Jan. 24, 2020, 2:07 p.m. OK GNU C++17 TESTS 66 265 204800 3400
69464240 Ismoil_Pariso_Love H Jan. 24, 2020, 12:09 p.m. OK GNU C++17 TESTS 66 265 204800 3400
67185721 ecnerwala H Dec. 19, 2019, 4:29 a.m. OK GNU C++17 TESTS 64 280 204800 3400
67689518 dimas.kovas H Dec. 27, 2019, 10:27 a.m. OK GNU C++17 TESTS 66 608 409600 3400
67153580 paulica H Dec. 18, 2019, 11:43 a.m. OK GNU C++17 TESTS 64 1762 204800 3400
67153432 paulica H Dec. 18, 2019, 11:40 a.m. OK GNU C++17 TESTS 64 1778 307200 3400
67129881 vinhntndu H Dec. 17, 2019, 10:41 p.m. OK Java 11 TESTS 64 2074 46796800 3400
67118576 eatmore H Dec. 17, 2019, 5:30 p.m. OK Java 11 TESTS 64 2121 46796800 3400

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