Codeforces Round 136 (Div. 1)

Solutions for Codeforces Round 136 (Div. 1) (contest 220). 3/4 problems verified against sample I/O. Difficulty range: 1300-2500.

4 items

Codeforces Round 136 (Div. 1)

Type: Div. 1 | Problems: 4 | Verified: 3/4 | Rating range: 1300-2500 | Time: 8m 14s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Little Elephant and Problem	1300	implementation, sortings	2m 48s	✓
B	Little Elephant and Array	1800	constructive-algorithms, data-structures	1m 7s	✓
C	Little Elephant and Shifts	2100	data-structures	1m 54s	✓
D	Little Elephant and Triangle	2500	geometry, math	2m 25s	✗

Practice › Codeforces Solutions › Codeforces Round 136 (Div. 1) ›

CF 220A - Little Elephant and Problem

We are given an array of integers that is supposed to be sorted in non-decreasing order. The Little Elephant suspects that at most one swap operation may have disturbed the array.

Practice › Codeforces Solutions › Codeforces Round 136 (Div. 1) ›

CF 220B - Little Elephant and Array

We are given an array of positive integers and multiple queries, each specifying a contiguous subarray. For each query, we are asked to count how many numbers appear in the subarray exactly as many times as their own value.

Practice › Codeforces Solutions › Codeforces Round 136 (Div. 1) ›

CF 220C - Little Elephant and Shifts

We have two permutations of the numbers from 1 to n. For every cyclic rotation of permutation b, we must compute how close the rotated permutation can align with permutation a. For a fixed pair of permutations, the distance is defined using matching values.

Practice › Codeforces Solutions › Codeforces Round 136 (Div. 1) ›

CF 220D - Little Elephant and Triangle

We work on the integer lattice inside a rectangle. Every point $(x,y)$ with $0 le x le w$ and $0 le y le h$ is available. We must count ordered triples of distinct lattice points that form a nondegenerate triangle whose area is an integer.