Codeforces Round 183 (Div. 1)

5 problems from Codeforces Round 183 (Div. 1) (contest 303), difficulty 1300-3000. 3/5 solutions verified against sample I/O.

5 items

Codeforces Round 183 (Div. 1)

Div. 1 | 5 problems | 3/5 verified | Difficulty 1300-3000 | 15m 59s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Lucky Permutation Triple	1300	constructive-algorithms, implementation, math	8,568	2m 15s
B	Rectangle Puzzle II	1700	implementation, math	1,424	3m 45s	✓
C	Minimum Modular	2400	brute-force, graphs, math	967	4m 56s	✓
D	Rotatable Number	2600	math, number-theory	352	1m 56s	✓
E	Random Ranking	3000	dp, math, probabilities	383	3m 7s

Practice › Codeforces Solutions › Codeforces Round 183 (Div. 1) ›

CF 303A - Lucky Permutation Triple

We are asked to construct three permutations $a$, $b$, and $c$ of length $n$ such that for every index $i$ the sum of $a[i]$ and $b[i]$ modulo $n$ equals $c[i]$ modulo $n$.

Practice › Codeforces Solutions › Codeforces Round 183 (Div. 1) ›

CF 303B - Rectangle Puzzle II

We have a grid-aligned rectangle of size n × m. Every valid point has integer coordinates between (0, 0) and (n, m). We must choose another axis-aligned rectangle inside it. The rectangle is described by four integers (x1, y1, x2, y2).

Practice › Codeforces Solutions › Codeforces Round 183 (Div. 1) ›

CF 303C - Minimum Modular

We are given a set of distinct integers. We may delete at most k of them, where k ≤ 4. After deleting, we want all remaining numbers to produce different remainders modulo some positive integer m. Two numbers collide modulo m exactly when their difference is divisible by m.

Practice › Codeforces Solutions › Codeforces Round 183 (Div. 1) ›

CF 303D - Rotatable Number

We are looking for bases in which a very special cyclic behavior exists. Take a number with exactly n digits in base b. Leading zeroes are allowed, so 0011 in base 2 is a valid length-4 number.

Practice › Codeforces Solutions › Codeforces Round 183 (Div. 1) ›

CF 303E - Random Ranking

Each participant receives a real-valued score chosen uniformly from an interval $[li, ri]$. Scores are independent. After all scores are generated, participants are sorted by score. Smaller score means better rank, so the participant with the largest score finishes last.