We discuss the Euclidean algorithm that finds the greatest common divisor of 2 numbers u and v. We want to extend and compute the gcd of n integers gcd(u_1,u_2,….u_n). One way to do it is to assume all numbers are non-negative, so if only one of if u_j≠0 it is the gcd. Otherwise replace u_k by u_k mod u_j for all k≠j where u_j is the minimum of the non-zero elements (u’s). The algorithm can be made significantly faster if one consider the identity: gcd(u_1,u_2….u_n )=gcd(u_1,gcd(u_2,u_3,..u_n )). Then we may calculate gcd(u_1,u_2….u_n ) with following algorithm: Step 1. set d←u_n,j←n-1 Step 2. if d≠1 and j>0 set gcd(u_j,d)and j=j-1 and repeat Step 2. Else d=gcd(u_1,u_2,…u_n). What is the sma`llest value of u_n such that the calculation of: gcd(u_1,u_2,...,u_n) by steps Step 1 and Step 2 (given above) requires N divisions, if Euclid’s algorithm is used throughout? Assume that N ≥ n.
The following java code can be used to find the gcd of array of elements:
public class GCD{
static int gcd(int x,int y) //GCD of two numbers
{
if (x==0)
return y;
return gcd(y%x,x);
}
static int findgcd(int arr[], int n)//Function to find gcd of array
of numbers. Ex:gcd(u_1,u_2,…,u_n).
{
int result = arr[0];
for (int i=1;i<n;i++){
result=gcd(arr[i],result);
if(result==1)
{
return 1;
}
}
return result;
}
public static void main(String args[])
{
int arr[] = {2,4,6,26,45}; //Input elemets
//you can write a loop to get the inputs as per user
requirement
int n=arr.length;
System.out.println(findgcd(arr,n));//Array elements and array
length are passed as arguments
}
}
We discuss the Euclidean algorithm that finds the greatest common divisor of 2 numbers u and...
We discuss the Euclidean algorithm that finds the greatest common divisor of 2 numbers u and v. We want to extend and compute the gcd of n integers gcd(u1,u2,….un). One way to do it is to assume all numbers are non-negative, so if only one of if uj≠0 it is the gcd. Otherwise replace uk by uk mod uj for all k≠j where uj is the minimum of the non-zero elements (u’s). The algorithm can be made significantly faster if one...
a Find the greatest common divisor (gcd) of 322 and 196 by using the Euclidean Algorithm. gcd- By working back in the Euclidean Algorithm, express the gcd in the form 322m196n where m and n are integers b) c) Decide which of the following equations have integer solutions. (i) 322z +196y 42 ii) 322z +196y-57
Write down the Euclidean algorithm then use the algorithm to find the greatest common divisor of the following pairs of numbers. 315, 825 2091, 4807
20 points Problem 4: Extended Euclidean Algorithm Using Extended Euclidean Algorithm compute the greatest common divisor and Bézout's coefficients for the pairs of integer numbers a and b below. Express the greatest common divisor as a linear combination with integer coefficients) of a and b. (Do not use factorizations or inspection. Please demonstrate all steps of the Extended Euclidean Algo- rithm.) (a) a 270 and b = 219 (b) a 869 and b 605 (c) a 4930 and b-1292 (d)...
Question 1. (a) Find the greatest common divisor of 10098 and 3597 using the Euclidean Algorithm. (b) Find integers a and a2 with 1009801 +3597a2 = gcd(10098,3597). (c) Are there integers bı and b2 with 10098b1 + 3597b2 = 71? Justify your answer. (d) Are there integers ci and c2 with 10098c1 + 3597c2 = 99? Justify your answer. Question 2. Consider the following congruence. C: 21.- 34 = 15 (mod 521) (a) Find all solutions x € Z to...
Using SPIM, write and test a program that finds the Greatest Common Divisor of two integers using a recursive function that implements Euclid's GCD algorithm as described below. Your program should greet the user "Euclid's GCD algorithm", prompt the user to input two integers, and then output the result "Euclid's Greatest Common Divisor Algorithm" GCD(M,N) = M (if N is 0) GCD(M,N) = GCD(N, M % N) (if N > 0) you may assume that inputs are non-negative name your assembly...
1. (10 points) GCD Algorithm The greatest common divisor of two integers a and b where a 2 b is equal to the greatest common divisor of b and (a mod b). Write a program that implements this algorithm to find the GCD of two integers. Assume that both integers are positive. Follow this algorithm: 1. Call the two integers large and small. 2. If small is equal to 0: stop: large is the GCD. 3. Else, divide large by...
IN PYTHON Write a recursive function for Euclid's algorithm to find the greatest common divisor (gcd) of two positive integers. gcd is the largest integer that divides evenly into both of them. For example, the gcd(102, 68) = 34. You may recall learning about the greatest common divisor when you learned to reduce fractions. For example, we can simplify 68/102 to 2/3 by dividing both numerator and denominator by 34, their gcd. Finding the gcd of huge numbers is an...
Cryptography Computer Security Greatest Common Divisor Assignment Instructions In software, implement the Euclidean algorithm to find the greatest common divisor of any two positive integers. It should implement the pseudocode provided in the text. It should allow the user to enter two integers. Your program should output the intermediate values of q, r1, r2 for each step and should return the greatest common divisor. Challenge component: Allow the user's input to be zero as well as the positive integers. Provide...
Use the Division Algorithm to find the greatest common divisor of each pair of numbers below and determine whether each pair is rela- tively prime or not. Then reverse the process and write the gcd as a sum of multiples of the original pair. a. 12 and 15 b. 36 and 72 c. 27 and 10 d. 35 and 12