Loop / Boolean - Find Greatest Common Divisor Of Two Integers
Sep 25, 2014
In attempting to find the greatest common divisor (gcd) of two integers, n1 and n2, whereas k is a possible gcd and gcd is initialized to 1, the following code has been entered:
for (int k = 2; k <= n1 && k <= n2; k++) {
if ( n1 % 2 == 0 && n2 % 2 == 0)
gcd= k;
}
When asked to change the previous line of code to this:
for (int k = 2; k <= n1 / 2 && k < n2 / 2; k++){
the questions states this revision is wrong and to find the reason.....well, I've changed it, entered "3" (per the answer key) for n1 and n2....
now I can see logically where k (2 in this example) is not <= n1/2, which is 3/2 or 1, since we're dealing w/integers, yet when I compile and run, my answer is indeed, gcd = 1. However, since this is a Boolean expression where && is being used, since the first portion evaluates to "false", the 2nd portion isn't executed and thus my result of 1?...... loops are throwing me for one, for sure....
I have two ArrayLists and I want to compare them for common elements, and based on the result I want to update the first Arraylist to only have these elements. sort of like the opposite of RemoveAll() which removes elements in common and keep the ones that are unique. so far I thought of using for loop and .contains() in case it was fault,element not present, remove from list. but I was wondering in what other ways, perhaps APIs i can use to do that?
I need to create an algorithm that finds the common element(s) in all arrays that has a signature of public Comparable[] findCommonElements(Object[] collection) that has an efficiency of at most O(knlogn), uses a query array, and accepts as input a collection of arrays. I am aware my time would be better spent learning how to use array lists and hash sets, but I am supposed to use concepts already covered, and these have not been.
I feel like this code should work, but it is returning null for the array of common elements. Which means it obviously is not working correctly. I am also likely going to need implementing the sort algorithm, but I wanted to get the part of finding the common elements set first.
public class CommonElements2<T extends Comparable<T>> { Comparable[] tempArr; Comparable[] common; Comparable[] queryArray; /* sort algorithm goes here */ public Comparable[] findCommonElements(Object[] collections)
Inside a While Loop (While Loop begins if a condition is True) I have an If Statement, the else part of the statement assigns False to the condition I mentioned earlier.
But I've tried de-bugging and even when the code goes through the else part of the statement, firstly it returns False but then it returns to the beginning of the loop as True again.
Create a loop where you add the integers from 1 to 50.
public class Sum50 { public static void main(String[] args) { int sum = 0; int max = 50; for(int i = 0;i <= max; i++){ sum=sum+i; } System.out.println("Sum is " + sum); } }
I need to write a class in that uses the For loop and does the following things: asks user to input two integers, the second larger than the first. Next, use a for loop to sum the numbers between the two integers, including the original integer. For example: 5&8 would be 5+6+7+8 and lastly prints out the sum of this.
I have successfully been able to do the first part but when it comes to the For Loop I am a bit lost here is what I have so far
import java.util.Scanner; public class Question3 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Please enter an integer"); int num1 =sc.nextInt(); System.out.println("please enter a larger integer"); int num2=sc.nextInt(); int sum=0; for(int i=num1; i<=num2;i++); } }
Write a program that finds both the largest and smallest of several integers. T. For example, a program that determines the winner and loser of a sales contest would input the number of units sold by each salesperson. The salesperson who sells the most units wins the contest; the salesperson who sells the least units loses the contest. Write a pseudocode program, then a Java program that inputs a series of 10 integers and determines and prints the largest integer and the smallest integer. Your program should use at least the following four variables: counter, number , largest and smallest. After i run the code i just get the largest input without the smallest .
This is my code :
import java.util.Scanner; // program uses scanner // main Class begins public class Largest12 { public static void main(String[] args) //main method begins { //Initial variables int counter = 0; // initiate counter int number=0 ;
I have this code running correctly in Eclipse all except that it seems no matter where I declare, highest, lowest, average they always seem to stay at "0". I have a feeling the location of the Initialization is not the error since I have tried moving it to inside differ loops.
Stipulations on writing this code are:
Note: You do not need to use array to save each input score for this lab. A Single loop to read in each grade, compare with the current highest grade, lowest grade, and calculate the running sum at the same time.
import java.util.Scanner;
/*Write a program that prompts the user to enter the total number of students first. *Then ask the user to input each student’s grade and use loop statements to read in each grade. *Check input grade to make sure 0<=grade<=100, if the user input any other number, print out warning message and ask the user to input a new grade. Display the highest score, the lowest score and the average. */
public class LoopStatements { // Main Method public static void main(String[] args) { // Initialize int grade = 0; // grade value
1. Prompt the user to input two positive integers: firstNum and secondNum (firstNum must be smaller than secondNum). 2. Output all the even numbers between firstNum and secondNum inclusive. 3. Output the sum of all the even numbers between firstNum and secondNum inclusive. 4. Output all the odd numbers between firstNum and secondNum inclusive. 5. Output the sum of all the odd numbers between firstNum and secondNum inclusive.
*Use while loop int firstNum, secondNum; Scanner keyboard = new Scanner(System.in); System.out.println("Enter an integer: "); firstNum = keyboard.nextInt();
[Code] ....
What to do with the while loop and how to find even and odd numbers.
I'm required to create a program that finds the minimum value in an Array of integers.
Here is my approach :
public class Person { public static void main(String [ ] args){ int theArray[]=new int [10]; int result = 0; for (int i:theArray){ if (i < Integer.MAX_VALUE)
[Code]...
I can't really progress from this position. I keep getting told to change the return type to int on main method, then when i do it says change it to void..
I wrote this simple piece of code to find the number in the given array of Integers. The program works fine although it shows a couple of errors when i modify it a little bit.
public class DemoLabel{ public static void main(String [] args){ int[][] arrofInts={ {32,45,67,87}, {23,44,55,66}, {12,47,87,56}, {23,44,12,78}
[Code] .....
In the disp() method,Suppose i only want to pass two arguments i.e disp(i,j) given that searchFor variable is visible in the entire class but when i use disp(i,j) i get the following error
DemoLabel.java:38: error: cannot find symbol System.out.println("The number "+searchFor+" is at the location"+i+" , "+j); ^ symbol: variable searchFor location: class DemoLabel
So i decided to declare the
int searchFor as public int searchFor
But the compiler threw another error saying that it was a Illegal start of expression
Also,when i add a SOP line after the label search: it shows the error
working on assignment to count the total integers and have a seperate system.out if a non integer.
import java.util.Scanner; public class CountInteger { public static void main(String[] args) { int correctCount = -1 ; // count number of integers int data; int sum = 0;
import java.util.Scanner; public class Project_5 { public static void main (String[] args) { Scanner input= new Scanner (System.in);
[code]....
So I'm attempting to have this program take the users input of integers, pressing enter in between each one. If they enter a negative number it lets them know that its invalid. At the end of the program it takes all of the valid integers entered and must add them and average them. I've put the final println in there as a placeholder. If the user types in "6" then presses enter and types in "3" , the output is:
There were 3 valid numbers entered. The sum of the valid numbers was --- and the average was ---. There were 0 invalid numbers entered.
It then continues on allowing the user to enter more values. Here is the example output for correct code"
Enter a positive value (EOF to quit): 4 Enter a positive value (EOF to quit): 7 Enter a positive value (EOF to quit): 8 Enter a positive value (EOF to quit): 2 Enter a positive value (EOF to quit): -1 The number "-1" is invalid.
Enter a positive value (EOF to quit): 8 Enter a positive value (EOF to quit): 0 Enter a positive value (EOF to quit): -4 The number "-4" is invalid.
Enter a positive value (EOF to quit): CTRL-D
There were 6 valid numbers entered. The sum of the valid numbers was 29 and the average was 4.83. There were 2 invalid numbers.
I am trying to find 3 largest numbers in an array using a single For loop but my following code is still showing randomly sorted numbers.
public class largest3 { static int m, n, o; static int array[] = new int[100]; public static void main(String[] args) { for (int i = 0; i < 10; i++) { array[i] = (int) (Math.random() * 100);
import java.util.Scanner; public class AvgLrgSml{ public static void main(String[]args){ System.out.print("Hello there. Please enter any three numbers."); Scanner keyboard = new Scanner(System.in); double num1 = keyboard.nextDouble(); double num2 = keyboard.nextDouble();
I am trying to make a code that takes a list and puts the list in sorted order (least to greatest).
public class SortedIntList { static final int capacity = 10; private int [] data; private boolean unique; private int size; public SortedIntList(){ size =0; data = new int [10];
[Code] ....
Here what the code produces.
Testing SortedIntList() error when adding these values to list: 4 6 4 list should = [4, 4, 6] actual list = [4, 6, 4] was working properly prior to adding last value of 4