Introduction To Algorithms, Third Edition (international Edition)
Introduction To Algorithms, Third Edition (international Edition)
3rd Edition
ISBN: 9780262533058
Author: Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, Clifford Stein
Publisher: TRILITERAL
bartleby

Concept explainers

Question
Book Icon
Chapter D, Problem 2P

a.

Program Plan Intro

To prove that |R(A)|=2r and conclude that A defines a permutation on Sn only if A has full rank.

Given information:

  • r is the rank of matrix A.
  • Preimage of y is defined by P(A,y)={x:Ax=y} , for given n×n matrix A and given a value yR(A) .

Explanation:

It can be assumed without generality loss, that the first r columns of A are linearly independent.

Then for x1,x3Sn , it can be concluded that Ax1Ax2 based on following two conditions.

  • In the first r entries x1 and x2 are not identical. And x1 , x2
  • have 0’s in the remaining entries.

Now Ax1Ax2 is true since the first r entries of each are a linear combination of the first r rows of A , and it is impossible to have two different linear combinations that are equal of them because they are independent.

Now it is must that |R(A)|2r as there are at least 2r non-equivalent vectors xSn . Alternatively, x is a vector that doesn’t consists of 0’s in the coordinates that larger than r . Therefore Ax=xiai where ai is the ith column of A . Now as each of the last nr columns of A is in fact a linear combination of the first r columns of A , this can be rewritten as a linear combination of the first r columns of A .

Since all of these has been already, |R(A)|=2r . The range cannot include all 2n elements of Sn if A doesn’t have full rank so, permutation can be defined possible by A

b.

Program Plan Intro

To prove that |P(A,y)|=2nr if r is the rank of n×n matrix A and yR(A) .

c.

Program Plan Intro

To prove that |B(S',m)|=2r and that for each block in B(S',m) exactly 2mr numbers in S map to that block.

d.

Program Plan Intro

To show that number of linear permutations of Sn is much less than number of permutations of S using counting argument.

e.

Program Plan Intro

To provide an example of a value n and permutation of Sn that cannot be achieved by any linear permutation.

Blurred answer
Students have asked these similar questions
How can I resolve the following issue?
I need help to resolve, thank you.
Let the user choose encryption or decryption. For encryption, let user input the key in Hexadecimal number, the plain text in Hexadecimal number, output the ciphertext (in hexadecimal numbers). For decryption, let user input the key in Hexadecimal number, the ciphertext (in hexadecimal numbers), output the decrypted message (Hexadecimal number). Both encryption and decryption should output the different operation results for each round like the following: For example: Round 1: E(R0) = ...... (Hex or Binary) K1 = …… E(Ro) xor K1 = S-box outputs = …… f(Ro1, K1) = ….. L2 =R1 =……. La = Ra Round 2: .....• No Encryption/Decryption libraries or functions provided by the third party are allowed. Submit your program codes to Moodle with the notes of how to compile and run your program.
Knowledge Booster
Background pattern image
Computer Science
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
C++ for Engineers and Scientists
Computer Science
ISBN:9781133187844
Author:Bronson, Gary J.
Publisher:Course Technology Ptr
Text book image
Operations Research : Applications and Algorithms
Computer Science
ISBN:9780534380588
Author:Wayne L. Winston
Publisher:Brooks Cole
Text book image
Systems Architecture
Computer Science
ISBN:9781305080195
Author:Stephen D. Burd
Publisher:Cengage Learning
Text book image
C++ Programming: From Problem Analysis to Program...
Computer Science
ISBN:9781337102087
Author:D. S. Malik
Publisher:Cengage Learning
Text book image
EBK JAVA PROGRAMMING
Computer Science
ISBN:9781337671385
Author:FARRELL
Publisher:CENGAGE LEARNING - CONSIGNMENT
Text book image
Programming Logic & Design Comprehensive
Computer Science
ISBN:9781337669405
Author:FARRELL
Publisher:Cengage