Codeforces Round 102 (Div. 1)

5 problems from Codeforces Round 102 (Div. 1) (contest 142), difficulty 1600-3000. 5/5 solutions verified against sample I/O.

5 items

Codeforces Round 102 (Div. 1)

Div. 1 | 5 problems | 5/5 verified | Difficulty 1600-3000 | 13m 21s

# Problem Rating Tags Accepted Time ✓
A Help Farmer 1600 brute-force, math 2,844 1m 53s ✓
B Help General 1800 constructive-algorithms, greedy, implementation 2,405 1m 38s ✓
C Help Caretaker 2300 brute-force, dp 997 1m 30s ✓
D Help Shrek and Donkey 2 2600 games 403 2m 34s ✓
E Help Greg the Dwarf 2 3000 geometry 92 5m 46s ✓
Practice › Codeforces Solutions › Codeforces Round 102 (Div. 1) ›

CF 142A - Help Farmer

After the theft, the barn contains a smaller rectangular box of hay blocks. If the original dimensions were $A times B times C$, then the remaining pile has dimensions $(A-1) times (B-2) times (C-2)$.
codeforces competitive-programming brute-force math May 29, 2026
Practice › Codeforces Solutions › Codeforces Round 102 (Div. 1) ›

CF 142B - Help General

We have an n × m chessboard-like grid, and we want to place as many soldiers as possible. Two soldiers conflict if the squared Euclidean distance between their cells is exactly 5. The only integer pairs whose squared distance equals 5 are (1, 2) and (2, 1) up to sign.
codeforces competitive-programming constructive-algorithms greedy implementation May 29, 2026
Practice › Codeforces Solutions › Codeforces Round 102 (Div. 1) ›

CF 142C - Help Caretaker

We are tasked with filling a warehouse grid of size n by m with the maximum number of T-shaped turboplows. Each turboplow occupies five cells in a specific T pattern, but it can be rotated in any of four orientations.
codeforces competitive-programming brute-force dp May 29, 2026
Practice › Codeforces Solutions › Codeforces Round 102 (Div. 1) ›

CF 142D - Help Shrek and Donkey 2

We are asked to analyze a two-player game on a rectangular grid where each cell may contain a toy soldier from Shrek (green) or Donkey (red), or be empty. The grid has dimensions n × m, and on each row there are at most two soldiers.
codeforces competitive-programming games May 29, 2026
Practice › Codeforces Solutions › Codeforces Round 102 (Div. 1) ›

CF 142E - Help Greg the Dwarf 2

We are asked to find the shortest distance between two points on a cone, where the cone has a circular base of radius r and height h, and the points may lie anywhere on the cone's lateral surface or the base.
codeforces competitive-programming geometry May 29, 2026