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Let lowbit(x)lowbitโก(๐‘ฅ) denote the value of the lowest binary bit of x๐‘ฅ, e.g. lowbit(12)=4lowbitโก(12)=4, lowbit(8)=8lowbitโก(8)=8.For an array a๐‘Ž of length n๐‘›, if an array s๐‘  of length n๐‘› satisfies sk=(โˆ‘i=kโˆ’lowbit(k)+1kai)mod998244353๐‘ ๐‘˜=(โˆ‘๐‘–=๐‘˜โˆ’lowbitโก(๐‘˜)+1๐‘˜๐‘Ž๐‘–)mod998244353 for all k๐‘˜, then s๐‘  is called the Fenwick Tree of a๐‘Ž. Let's denote it as s=f(a)๐‘ =๐‘“(๐‘Ž).For a positive integer k๐‘˜ and an array a๐‘Ž, fk(a)๐‘“๐‘˜(๐‘Ž) is defined as follows:fk(a)={f(a)f(fkโˆ’1(a))ifย k=1otherwise.๐‘“๐‘˜(๐‘Ž)={๐‘“(๐‘Ž)ifย ๐‘˜=1๐‘“(๐‘“๐‘˜โˆ’1(๐‘Ž))otherwise.You are given an array b๐‘ of length n๐‘› and a positive integer k๐‘˜. Find an array a๐‘Ž that satisfies 0โ‰คai<9982443530โ‰ค๐‘Ž๐‘–<998244353 and fk(a)=b๐‘“๐‘˜(๐‘Ž)=๐‘. It can be proved that an answer always exists. If there are multiple possible answers, you may print any of them.InputEach test contains multiple test cases. The first line contains the number of test cases t๐‘ก (1โ‰คtโ‰ค1041โ‰ค๐‘กโ‰ค104). The description of the test cases follows.The first line of each test case contains two positive integers n๐‘› (1โ‰คnโ‰ค2โ‹…1051โ‰ค๐‘›โ‰ค2โ‹…105) and k๐‘˜ (1โ‰คkโ‰ค1091โ‰ค๐‘˜โ‰ค109), representing the length of the array and the number of times the function f๐‘“ is performed.The second line of each test case contains an array b๐‘ of length n๐‘› (0โ‰คbi<9982443530โ‰ค๐‘๐‘–<998244353).It is guaranteed that the sum of n๐‘› over all test cases does not exceed 2โ‹…1052โ‹…105.OutputFor each test case, print a single line, containing a valid array a๐‘Ž of length n๐‘›.ExampleinputCopy28 11 2 1 4 1 2 1 86 21 4 3 17 5 16outputCopy1 1 1 1 1 1 1 11 2 3 4 5 6

Question

Let lowbit(x)lowbitโก(๐‘ฅ) denote the value of the lowest binary bit of x๐‘ฅ, e.g. lowbit(12)=4lowbitโก(12)=4, lowbit(8)=8lowbitโก(8)=8.For an array a๐‘Ž of length n๐‘›, if an array s๐‘  of length n๐‘› satisfies sk=(โˆ‘i=kโˆ’lowbit(k)+1kai)mod998244353๐‘ ๐‘˜=(โˆ‘๐‘–=๐‘˜โˆ’lowbitโก(๐‘˜)+1๐‘˜๐‘Ž๐‘–)mod998244353 for all k๐‘˜, then s๐‘  is called the Fenwick Tree of a๐‘Ž. Let's denote it as s=f(a)๐‘ =๐‘“(๐‘Ž).For a positive integer k๐‘˜ and an array a๐‘Ž, fk(a)๐‘“๐‘˜(๐‘Ž) is defined as follows:fk(a)={f(a)f(fkโˆ’1(a))ifย k=1otherwise.๐‘“๐‘˜(๐‘Ž)={๐‘“(๐‘Ž)ifย ๐‘˜=1๐‘“(๐‘“๐‘˜โˆ’1(๐‘Ž))otherwise.You are given an array b๐‘ of length n๐‘› and a positive integer k๐‘˜. Find an array a๐‘Ž that satisfies 0โ‰คai<9982443530โ‰ค๐‘Ž๐‘–<998244353 and fk(a)=b๐‘“๐‘˜(๐‘Ž)=๐‘. It can be proved that an answer always exists. If there are multiple possible answers, you may print any of them.InputEach test contains multiple test cases. The first line contains the number of test cases t๐‘ก (1โ‰คtโ‰ค1041โ‰ค๐‘กโ‰ค104). The description of the test cases follows.The first line of each test case contains two positive integers n๐‘› (1โ‰คnโ‰ค2โ‹…1051โ‰ค๐‘›โ‰ค2โ‹…105) and k๐‘˜ (1โ‰คkโ‰ค1091โ‰ค๐‘˜โ‰ค109), representing the length of the array and the number of times the function f๐‘“ is performed.The second line of each test case contains an array b๐‘ of length n๐‘› (0โ‰คbi<9982443530โ‰ค๐‘๐‘–<998244353).It is guaranteed that the sum of n๐‘› over all test cases does not exceed 2โ‹…1052โ‹…105.OutputFor each test case, print a single line, containing a valid array a๐‘Ž of length n๐‘›.ExampleinputCopy28 11 2 1 4 1 2 1 86 21 4 3 17 5 16outputCopy1 1 1 1 1 1 1 11 2 3 4 5 6

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Solution

This problem is a programming problem that involves the concept of Fenwick Trees, also known as Binary Indexed Trees. The problem is to find an array 'a' that satisfies certain conditions given an array 'b' and a positive integer 'k'.

Here are the steps to solve this problem:

  1. Understand the problem: The problem is asking to find an array 'a' such that when a function 'f' is applied 'k' times on 'a', it results in the array 'b'. The function 'f' is defined as the Fenwick Tree of the array.

  2. Understand the function 'f': The function 'f' is defined as a Fenwick Tree of an array. A Fenwick Tree is a data structure that provides efficient methods for calculation and manipulation of the prefix sums of a table of values.

  3. Understand the constraints: The elements of the array 'a' should be less than 998244353 and the array 'b' is given. The number of times the function 'f' is applied is also given.

  4. Approach to solve: Since the problem guarantees that a solution always exists, one possible approach is to start with an array 'a' that is the same as 'b'. Then, apply the function 'f' 'k' times on 'a' and check if it results in 'b'. If it does, then 'a' is the solution. If not, modify 'a' and repeat the process.

  5. Implement the solution: This step involves coding the solution in a programming language. The problem does not specify a particular programming language, so you can use any language you are comfortable with.

  6. Test the solution: After implementing the solution, test it with various test cases to ensure it works as expected. The problem provides some test cases that you can use.

Remember, this is a competitive programming problem, so the efficiency of your solution is important. You should aim for a solution that solves the problem in the least amount of time and using the least amount of memory.

This problem has been solved

Similar Questions

A binary tree should have at least

binary tree should have at least

Square StringThe sqing value for a binary string ๐‘†S of length ๐‘N is calculated as follows:Let ๐‘‹=0X=0 be the initial sqing value.For each ๐‘–i from 11 to ๐‘N, let ๐‘—j be the largest index such that 1โ‰ค๐‘—<๐‘–1โ‰คj<i and ๐‘†๐‘—โ‰ ๐‘†๐‘–S jโ€‹ ๎€ =S iโ€‹ .If such an index ๐‘—j exists, add (๐‘–โˆ’๐‘—)2(iโˆ’j) 2 to ๐‘‹X, otherwise do nothing.For example, consider ๐‘†=000110S=000110.For ๐‘–=1,2,3i=1,2,3, there is no ๐‘—<๐‘–j<i such that ๐‘†๐‘—โ‰ ๐‘†๐‘–S jโ€‹ ๎€ =S iโ€‹ .For ๐‘–=4i=4 and ๐‘–=5i=5, we find ๐‘—=3j=3, and add (4โˆ’3)2=1(4โˆ’3) 2 =1 and (5โˆ’3)2=4(5โˆ’3) 2 =4 to the answer, respectively.For ๐‘–=6i=6, we find ๐‘—=5j=5 and add (6โˆ’5)2=1(6โˆ’5) 2 =1 to the answer.The sqing value is thus 1+4+1=61+4+1=6.You are given ๐‘N. There are 2๐‘2 N binary strings of length ๐‘N.Find the sum of all their sqing values.This sum can be large, so compute it modulo 109+710 9 +7.As a reminder, a binary string is a string whose characters are all either 00 or 11.Input FormatThe first line of input will contain a single integer ๐‘‡T, denoting the number of test cases.The first and only line of each test case contains a single integer ๐‘N โ€” the length of the binary strings to be considered.Output FormatFor each test case, output on a new line the answer, modulo 109+710 9 +7.Constraints1โ‰ค๐‘‡โ‰ค10001โ‰คTโ‰ค10001โ‰ค๐‘โ‰ค5โ‹…1051โ‰คNโ‰ค5โ‹…10 5 The sum of ๐‘N over all test cases won't exceed 5โ‹…1055โ‹…10 5 .Sample 1:InputOutput323838216839372959Explanation:Test case 11: The possible strings are {"00","01","10","11"}{"00","01","10","11"}.The sqing value for "00""00" is 00.The sqing value for "01""01" is 11 (for ๐‘–=2i=2, we find ๐‘—=1j=1).The sqing value for "10""10" is 11 (for ๐‘–=2i=2, we find ๐‘—=1j=1).The sqing value for "11""11" is 00.Hence, the answer to this test case is 22.Test case 22: There are 88 binary strings of length 33.The sqing value for "000""000" is 00The sqing value for "001""001" is 11The sqing value for "010""010" is 22The sqing value for "011""011" is 55The sqing value for "100""100" is 55The sqing value for "101""101" is 22The sqing value for "110""110" is 11The sqing value for "111""111" is 00Hence, the answer to this test case is 1616.

A binary tree in which all its levels except possibly the last, have the maximum number of nodes and all the nodes at the last level appear as far left as possible, is known as:

Today, Cat and Fox found an array a๐‘Ž consisting of n๐‘› non-negative integers.Define the loneliness of a๐‘Ž as the smallest positive integer k๐‘˜ (1โ‰คkโ‰คn1โ‰ค๐‘˜โ‰ค๐‘›) such that for any two positive integers i๐‘– and j๐‘— (1โ‰คi,jโ‰คnโˆ’k+11โ‰ค๐‘–,๐‘—โ‰ค๐‘›โˆ’๐‘˜+1), the following holds:ai|ai+1|โ€ฆ|ai+kโˆ’1=aj|aj+1|โ€ฆ|aj+kโˆ’1,๐‘Ž๐‘–|๐‘Ž๐‘–+1|โ€ฆ|๐‘Ž๐‘–+๐‘˜โˆ’1=๐‘Ž๐‘—|๐‘Ž๐‘—+1|โ€ฆ|๐‘Ž๐‘—+๐‘˜โˆ’1,where x|y๐‘ฅ|๐‘ฆ denotes the bitwise OR of x๐‘ฅ and y๐‘ฆ. In other words, for every k๐‘˜ consecutive elements, their bitwise OR should be the same. Note that the loneliness of a๐‘Ž is well-defined, because for k=n๐‘˜=๐‘› the condition is satisfied.Cat and Fox want to know how lonely the array a๐‘Ž is. Help them calculate the loneliness of the found array.InputEach test consists of multiple test cases. The first line contains a single integer t๐‘ก (1โ‰คtโ‰ค1041โ‰ค๐‘กโ‰ค104)ย โ€” the number of test cases. The description of the test cases follows.The first line of each test case contains one integer n๐‘› (1โ‰คnโ‰ค1051โ‰ค๐‘›โ‰ค105)ย โ€” the length of the array a๐‘Ž.The second line of each test case contains n๐‘› integers a1,a2,โ€ฆ,an๐‘Ž1,๐‘Ž2,โ€ฆ,๐‘Ž๐‘› (0โ‰คai<2200โ‰ค๐‘Ž๐‘–<220)ย โ€” the elements of the array.It is guaranteed that the sum of n๐‘› over all test cases doesn't exceed 105105.OutputFor each test case, print one integer ย โ€” the loneliness of the given array.ExampleinputCopy71032 2 231 0 253 0 1 4 252 0 4 0 270 0 0 0 1 2 480 1 3 2 2 1 0 3outputCopy1134473

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