Codeforces Round 644 (Div. 3)

8 problems from Codeforces Round 644 (Div. 3) (contest 1360), difficulty 800-2100. 6/8 solutions verified against sample I/O.

8 items

Codeforces Round 644 (Div. 3)

Div. 3 | 8 problems | 6/8 verified | Difficulty 800-2100 | 30m 13s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Minimal Square	800	greedy, math	57,075	1m 35s	✓
B	B	800	greedy, sortings	53,706	3m 38s	✓
C	Similar Pairs	1100	constructive-algorithms, graph-matchings, greedy	36,772	4m 42s	✓
D	D	1300	math, number theory	42,975	5m 7s	✓
E	Polygon	1300	dp, graphs, implementation	27,991	2m 9s	✓
F	Spy-string	1700	bitmasks, brute-force, constructive-algorithms	13,519	1m 13s
G	A/B Matrix	1900	constructive-algorithms, greedy, math	8,349	7m 12s
H	H	2100	binary search, bitmasks, brute force	4,861	4m 37s	✓

Practice › Codeforces Solutions › Codeforces Round 644 (Div. 3) ›

CF 1360F - Spy-string

We are given several strings of equal length, and we want to construct a new string of the same length. The requirement is that this constructed string must be extremely close to every given string: for each input string, it is allowed to differ from our constructed string in…

Practice › Codeforces Solutions › Codeforces Round 644 (Div. 3) ›

CF 1360G - A/B Matrix

We are asked to construct a binary grid of size $n times m$, where each cell is either 0 or 1, under two simultaneous constraints that tightly couple rows and columns. Every row must contain exactly $a$ ones, and every column must contain exactly $b$ ones.

Practice › Codeforces Solutions › Codeforces Round 644 (Div. 3) ›

CF 1360C - Similar Pairs

We are given several independent arrays, each with an even number of elements. For each array, we must decide whether it is possible to split all elements into disjoint pairs such that every number belongs to exactly one pair and each pair satisfies a compatibility rule.

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CF 1360E - Polygon

We are given an $n times n$ square matrix that starts entirely filled with zeros. Along the top edge, there are $n$ cannons, one above each column, and along the left edge, there are $n$ cannons, one to the left of each row.

Practice › Codeforces Solutions › Codeforces Round 644 (Div. 3) ›

CF 1360A - Minimal Square

We are asked to find the minimal square that can contain two identical rectangles of size $a times b$. The rectangles can be rotated, moved, and must remain entirely within the square, with sides parallel to the square.