Parameter Scenario p, a large prime 23 a, an integer in {2,3,..., p-2} 3 P=23 and a=3 are published Alice chooses a in {2,3,.., p-2} 5 ..... Bob chooses b in {2,3,..., p-2} 9 Alice computes A = aª mod p, its public key

Parameter Scenario p, a large prime 23 a, an integer in {2,3,..., p-2} 3 P=23 and a=3 are published Alice chooses a in {2,3,.., p-2} 5 ..... Bob chooses b in {2,3,..., p-2} 9 Alice computes A = aª mod p, its public key

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Suppose you generate the following RSA key pairs: • p = 37199• q = 49031• N = p · q = 1823904169• (p − 1) · (q − 1) = 1823817940• e = 65537 (for encryption)• d = 1578812933 (for decrption)Assuming a=01, b=02, . . . , z=26, and we group the digits in groups of three. (i) If someone wants to send the following message: “SELLALL” using your public key, what strings of digits should they send you (i.e., encrypt this message)?
Computing Values of a Hash FunctionInstead of 10,000 students, suppose there are only 6. Define a functionH, from the set of student ID numbers to the set {0, 1, 2, 3, 4, 5, 6,7, 8, 9, 10} as follows:H(n) = n mod 11 for each ID number n.To compute values of H either use a calculator or a computer with abuilt-in mod function or use the formula n mod 11 = n - (n div 11). Inother words, divide n by 11, multiply the integer part of the resultby 11, and subtract that number from n.As an example, since 328343419/11 = 29849401.73.H(328343419) = 328343419 - (11 * 29849401) = 8. To store the link tothe record for the student with ID number n, start by computing H(n).For instance, if the ID numbers are 328343419, 356633102, 223799061,607275830 and 513408716, calculate the hash values and comment in detailwith mathematical justification on the hash function.
(in java)- In class HashTable implement a hash table and consider the following:(i) Keys are integers (therefore also negative!) and should be stored in the tableint[] data.(ii) As a hash function take h(x) = (x · 701) mod 2000. The size of the table istherefore 2000. Be careful when computing the index of a negative key. Forexample, the index of the key x = −10 ish(−10) = (−7010) mod 2000 = (2000(−4) + 990) mod 2000 = 990.Hence, indices should be non-negative integers between 0 and 1999!(iii) Implement insert, which takes an integer and inserts it into a table. Themethod returns true, if the insertion is successful. If an element is already inthe table, the function insert should return false.(iv) Implement search, which takes an integer and finds it in the table. The methodreturns true, if the search is successful and false otherwise.(v) Implement delete, which takes an integer and deletes it form the table. Themethod returns true, if the deletion is successful and false…
A safe is locked by a combination of of four binary digits (that is, 0 or 1), but theowner has forgotten the combination. The safe is designed in such a way that nomatter how many digits have been pressed, if the correct combination of three digitsis pressed at any point, then the safe automatically opens (there is no ”enter” key).Our goal is to find the minimum number of digits that one needs to key in in order toguarantee that the safe opens. In other words, we wish to find the smallest possiblelength of a binary sequence containing every four-digit sequence in it.(a) Create a digraph whose vertex set consists of three-digit binary sequences. Fromeach vertex labelled xyz, there is one outgoing edge (labelled 0) leading to vertexyz0, and another outgoing edge (labelled 1) leading to vertex yz1.(b) Explain why every edge represents a four digit sequence and why an Euleriantour of this graph represents the desired sequence of keystrokes.(c) Find the minimum number of digits that one…
PLEASE PLEASE SHOW CALCULATIONS Using the Vigenere cipher given in class: ADQYS MIUSB OXKKT MIBHK IZOOO EQOOG IFBAG KAUMFVVTAA CIDTW MOCIO EQOOG BMBFV ZGGWP CIEKQ HSNEWVECNE DLAAV RWKXS VNSVP HCEUT QOIOF MEGJS WTPCHAJMOC HIUIX Determine the Keys that would be needed to decipher the given cipher given the following deductions made in class Key of length 6; alphabet 1: AIKHOIATTOBGEEERNEOSAI alphabet 2: DUKKEFUAWEMGKWDWSUFWJU alphabet 3: QSTIQBMAMQBWQVLKVTMTMI alphabet 4: YBMZOAFCOOFPHEAXPQEPOX alphabet 5: SOIOOGVICOVCSVASHOGCC alphabet 6: MXBOGKVDIGZINNVVCIJHH
A high school has 1000 students and 1000 lockers, one locker for each student. On the first day of school, theprincipal plays the following game: She asks the first student to open all the lockers. She then asks the secondstudent to close all the even-numbered lockers. The third student is asked to check every third locker. If it isopen, the student closes it; if it is closed, the student opens it. The fourth student is asked to check every fourthlocker. If it is open, the student closes it; if it is closed, the student opens it. The remaining students continuethis game. In general, the nth student checks every nth locker. If it is open, the student closes it; if it is closed,the student opens it. After all the students have taken turns, some of the lockers are open and some are closed.The program below, when ran, will prompt the user to enter the number of lockers in the school. After thegame is over, the program will output the number of lockers and the lockers numbers of the lockers…
Suppose you generate the following RSA key pairs:• p = 37199• q = 49031• N = p · q = 1823904169• (p − 1) · (q − 1) = 1823817940• e = 65537 (for encryption)• d = 1578812933 (for decrption)Assuming a=01, b=02, . . . , z=26, and we group the digits in groups of three. (ii) If you receive strings of digits from a sender: 199770170, 1288754980, 324346846, 1370682962, decrypt the message.
A hallway has 100 locked lockers. A guy begins by opening each of the 100 lockers.He then shuts every other locker. Then, on his third pass, he toggles every third locker (closes if open, opens if closed). This method is repeated for 100 passes, such that the man toggles every ith locker on each pass i. How many lockers are open after his 100th journey along the corridor, in which he toggles just locker #100?
TRANSLATE TO PYTHON import java.util.*; public class queen { finalprivateint [][] map = newint[8][8]; finalprivateint [][] testMap = newint[8][8]; privateintheuristic = 0; privateintqueenLocs = 0; privateintrestarts = 0; privateintmoves = 0; privateintneighbors = 8; publicqueen( ){ //initializes the map for(inti = 0; i < 8; i++){ for(intj = 0; j < 8; j++){ map[i][j] = 0; } } } publicvoidrandomizeMap( ){ //randomizes the map Randomrand = newRandom( ); intnum; while(queenLocs < 8){ for(inti = 0; i < 8; i++){ map[rand.nextInt(7)][i] = 1; queenLocs++; } } heuristic = heuristic(map); } //***************************Heuristic****************************// publicbooleanfindRowEx(int [][] test, inta){ //determines row conflicts booleanexFound = false; intcount = 0; for(inti = 0; i < 8; i++){ if(test[i][a] == 1){ count++; } } if(count > 1){ exFound = true; } returnexFound; } publicbooleanfindColEx(int [][] test, intj){ //determines column conflicts booleanexFound =…
a. Develop a Caesar cipher-type encryption algorithm with a little more complexity in it. For example, the algorithm could alternatively shift the cleartext letters positive and negative by the amount of the key value. Variations on this are limitless. b. Select a single-digit key. c. Code a short message using the algorithm and key. d. Give your instructor the algorithm, key, cleartext, and ciphertext. e. Optional: Your instructor will randomly redistribute to the class the ciphertext messages completed in part d above. You are to decode the message you receive as an additional assignment.
In class HashTable implement a hash table and consider the following:(i) Keys are integers (therefore also negative!) and should be stored in the tableint[] data.(ii) As a hash function take h(x) = (x · 701) mod 2000. The size of the table istherefore 2000. Be careful when computing the index of a negative key. Forexample, the index of the key x = −10 ish(−10) = (−7010) mod 2000 = (2000(−4) + 990) mod 2000 = 990.Hence, indices should be non-negative integers between 0 and 1999!(iii) Implement insert, which takes an integer and inserts it into a table. Themethod returns true, if the insertion is successful. If an element is already inthe table, the function insert should return false.(iv) Implement search, which takes an integer and finds it in the table. The methodreturns true, if the search is successful and false otherwise.(v) Implement delete, which takes an integer and deletes it form the table. Themethod returns true, if the deletion is successful and false otherwise.(vi)…
Write a program that uses a HashMap to compute a histogram of positivenumbers entered by the user. The HashMap’s key should be the numberthat is entered, and the value should be a counter of the number of timesthe key has been entered so far. Use −1 as a sentinel value to signal theend of user input. For example, if the user inputs:512355321-1then the program should output the following (not necessarily in this order):The number 3 occurs 2 times.The number 5 occurs 3 times.The number 12 occurs 1 times.The number 21 occurs 1 times.