Replay of Battle of Brains 2022, University of Dhaka

10 problems from Replay of Battle of Brains 2022, University of Dhaka (contest 104679), difficulty -. 9/10 solutions verified against sample I/O.

10 items

Replay of Battle of Brains 2022, University of Dhaka

Special | 10 problems | 9/10 verified | Difficulty - | 7m 30s

#	Problem	Time	✓
A	First Year, Second Year	48s	✓
B	Even Out	52s	✓
C	Odd One Out	49s	✓
D	Yet Another Mysterious Array	43s	✓
E	Rasta Thamaye Dilo	53s	✓
F	Lucky Seats	43s	✓
G	Winter Gifts	44s	✓
H	A Dance with DS	42s	✓
I	Stairway To Heaven	25s
J	XORted	51s	✓

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679C - Odd One Out

We are given a range of integers $[L, R]$. For every integer $X$ in this range, we define a value $f(X)$ based on counting how many ordered pairs of positive integers $(a, b)$ satisfy a multiplicative condition involving $X$.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679I - Stairway To Heaven

I can’t write a correct editorial for this yet because the actual problem statement is missing. What you pasted only shows the title lines (“Stairway To Heaven”, “J XORted”) and empty Input/Output sections, but there is no description of what the task is, what…

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679J - XORted

We are given an array that is already sorted in non-decreasing order. For each query, we are given a segment of this array, and we are allowed to pick a single integer mask $X$ (with up to 20 bits) and XOR every element in that segment by $X$.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679H - A Dance with DS

We are given two integers. One is a fixed base-like parameter $k$, and the other is an upper bound $r$. For any non-negative integer $n$, we define a process: if $n$ is divisible by $k$, we divide it by $k$, otherwise we subtract 1.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679G - Winter Gifts

We are given two strings of equal length and an integer step size $k$. The allowed operation does not let us freely edit characters anywhere. Instead, we can pick two positions whose distance is exactly $k$, and copy the character from one position into the other.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679F - Lucky Seats

We are given two integers that describe a hidden set of distinct non-negative integers. One of these values is the bitwise OR of all elements in the set, and the other is the bitwise XOR of all elements in the same set.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679E - Rasta Thamaye Dilo

We are given a graph whose vertices are the integers from 2 up to n. Two vertices are connected by an edge exactly when one of the numbers divides the other.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679D - Yet Another Mysterious Array

The game is played on an array of positive integers. Two players alternate turns. On each turn, a player selects a prime number that divides at least one element of the array.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679B - Even Out

We are given an array of integers, and we are forced to perform exactly one operation: choose a single position and flip the sign of that element. After doing this once, we compute the sum of the entire array and check whether this sum is even.

Practice › Codeforces Solutions › Replay of Battle of Brains 2022, University of Dhaka ›

CF 104679A - First Year, Second Year

We are given two numbers that summarize an unknown pair of positive integers. One number represents their sum, and the other represents their difference, where the difference is taken as first minus second. From these two values, we need to reconstruct the original pair.