Codeforces Testing Round 3

3 problems from Codeforces Testing Round 3 (contest 134), difficulty 1200-2200. 2/3 solutions verified against sample I/O.

3 items

Codeforces Testing Round 3

Special | 3 problems | 2/3 verified | Difficulty 1200-2200 | 5m 24s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Average Numbers	1200	brute-force, implementation	4,792	1m 39s	✓
B	Pairs of Numbers	1900	brute-force, dfs-and-similar, math	2,483	1m 30s	✓
C	Swaps	2200	constructive-algorithms, graphs, greedy	575	2m 15s

Practice › Codeforces Solutions › Codeforces Testing Round 3 ›

CF 134A - Average Numbers

We are given an array of positive integers. For every position, we remove that element and compute the arithmetic mean of the remaining numbers. We must find all positions where the removed value itself is exactly equal to that mean. Suppose the array is [1, 2, 3, 4, 5].

Practice › Codeforces Solutions › Codeforces Testing Round 3 ›

CF 134B - Pairs of Numbers

We are asked to start with the number pair (1,1) and reach a pair where at least one of the numbers equals a given target n. At each step, we can add one number to the other to form a new pair. Concretely, if our current pair is (a, b), the next pair can be (a+b, b) or (a, a+b).

Practice › Codeforces Solutions › Codeforces Testing Round 3 ›

CF 134C - Swaps

Each player initially owns cards of exactly one color, their own color. Player i starts with a[i] cards, all of color i. During a swap, two players exchange one card each. A player may only give away cards of their own color, and may never receive a color they already possess.