School Regional Team Contest, Saratov, 2011

10 problems from School Regional Team Contest, Saratov, 2011 (contest 120), difficulty 1000-2200. 8/10 solutions verified against sample I/O.

10 items

School Regional Team Contest, Saratov, 2011

Special | 10 problems | 8/10 verified | Difficulty 1000-2200 | 16m 31s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Elevator	1000	brute-force, implementation, math	5,663	1m 26s	✓
B	Quiz League	1100	implementation	3,668	1m 21s	✓
C	Winnie-the-Pooh and honey	1100	implementation, math	3,947	1m 39s	✓
D	Three Sons	1400	brute-force	2,101	1m 35s	✓
E	Put Knight!	1400	games, math	2,963	1m 56s	✓
F	Spiders	1400	dp, greedy, trees	4,128	1m 11s	✓
G	Boom	1800	implementation	719	1m 17s	✓
H	Brevity is Soul of Wit	1800	graph-matchings	1,590	2m 33s
I	Luck is in Numbers	2200	greedy	316	1m 27s	✓
J	Minimum Sum	1900	divide-and-conquer, geometry, sortings	1,024	2m 6s

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120A - Elevator

We are given two pieces of information about a person riding an elevator. The first input tells us which door the person used to enter, either the front door or the back door. The second input tells us which rail the person was holding, rail 1 or rail 2.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120B - Quiz League

We are given a circular table divided into n sectors, each containing a quiz question. Some questions have already been asked, marked with a 0, and others are still available, marked with a 1.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120C - Winnie-the-Pooh and honey

We have several jars of honey, and each jar starts with some amount of honey. Winnie repeatedly chooses the jar that currently contains the most honey. When Winnie picks a jar, two things may happen.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120D - Three Sons

We have a rectangular cornfield represented as a grid of size n × m, where each cell contains a certain number of tons of corn. The father wants to divide this field among three sons in such a way that each son receives exactly a predetermined amount of corn: A, B, or C tons.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120E - Put Knight!

We are asked to analyze a two-player game on an n × n chessboard. Petya and Gena take turns placing knights such that no knight can threaten another. A knight threatens positions in its standard L-shaped moves.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120F - Spiders

We are given a collection of toy spiders. Each spider is a tree, represented by beads (nodes) connected with strings (edges). A spider with $k$ beads has $k-1$ strings connecting its beads so that all beads are connected and there are no cycles.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120G - Boom

We are simulating a simplified version of the party game "Boom" with multiple teams and cards. There are n teams, each with two players. Each player has an ability to explain words (a) and an ability to understand words (b).

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120H - Brevity is Soul of Wit

We are given up to 200 distinct lowercase words. For every word, we must choose a short abbreviation whose length is between 1 and 4 characters, and whose characters appear in the original word in the same order.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120I - Luck is in Numbers

The problem asks us to find the next "lucky" ticket number that is strictly greater than a given ticket. Each ticket is a string of digits with even length, denoted 2n.

Practice › Codeforces Solutions › School Regional Team Contest, Saratov, 2011 ›

CF 120J - Minimum Sum

We are given a set of points in two-dimensional space, where each point can be thought of as a vector from the origin. Each vector has two coordinates, x and y, and we are allowed to independently flip the sign of each coordinate.