First time writing something here.
Why does my Subroutine not work?
I am trying to open the subroutine in the main function to get a boolean.
import java.util.Scanner;
public class Aufgabe1 {
public static void main(String[] args){
Scanner scan = new Scanner(System.in);
int eingabe = 0;
int zahl = 0;
boolean primzahl = false;
eingabe = scan.nextInt();//Input 1
if (eingabe == 1) {
zahl = scan.nextInt(); //Input 2
unterprogramm1(zahl);
}
public static boolean unterprogramm1(boolean primzahl) {
for (int i = 0; i < zahl; i++) {
if (zahl % i == 0) {
primzahl = true;
}
}
return primzahl;
}
You should write boolean primzahl in the parameter list, instead of just primzahl and move the method outside of the main function.
Related
I tried to check the palindrome number and find the single digit sum of the palindrome numbers, but my code is not returning the proper value (I am finding it difficult to return the value of sum from the loops). Can anyone help me getting the mistake. Any help will be appriciated.
import java.util.Scanner;
public class SumOfPalindrome {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of array elements");
int n = sc.nextInt();
int[] inp = new int[n];
System.out.println("enter the elements");
for(int i = 0; i< n ;i++)
{
inp[i] = sc.nextInt();
}
System.out.println(SumOfPalindromeNumber(inp));
}
private static int SumOfPalindromeNumber(int[] inp )
{
int sumpal =0;
for(int i = 0; i<inp.length;i++)
{
int rem =0;
int sum = 0;
while(inp[i]!=0)
{
rem = inp[i]%10;
sum=(sum*10)+rem;
inp[i]/=10;
}
if(inp[i]==sum)
{
sumpal+=inp[i];
if(sumpal>9)
{
sumpal=singledigitsum(sumpal);
}
}
}
return sumpal;
}
private static int singledigitsum(int sumpal)
{
int rem1 = 0;
int sum1 = 0;
while(sumpal!=0)
{
rem1=sumpal%10;
sum1+=rem1;
sumpal/=10;
}
if(sum1>9)
{
sum1=singledigitsum(sum1);
}
return sum1;
}
}
Enter numbers
Check which numbers are palindromes.
If that number is a palindrome then find sum of its digits.
Code:
import java.util.Scanner;
public class SumOfPalindrome {
public static void main(String[] args) {
SumOfPalindrome sumOfPalindrome=new SumOfPalindrome();
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of array elements");
int n = sc.nextInt();
int[] inp = new int[n];
System.out.println("enter the elements");
for(int i = 0; i< n ;i++)
{
inp[i] = sc.nextInt();
}
for(int i=0;i<n;i++)
{
if(sumOfPalindrome.isPallindrone(inp[i]))
{
System.out.println("No -> "+inp[i]+" Sum->"+sumOfPalindrome.sumOfDigits(inp[i]));
}
}
}//
public boolean isPallindrone(int no)
{
int r,sum=0,temp;
temp=no;
while(no>0){
r=no%10; //getting remainder
sum=(sum*10)+r;
no=no/10;
}
if(temp==sum)
{
return true;
}
else
{
return false;
}
}
public int sumOfDigits(int no)
{
int sum = 0;
while (no != 0)
{
sum = sum + no % 10;
no = no/10;
}
return sum;
}
}
I did not understand the purpose of sumpal in your code. You wanted a method which return sumOfPalindromes in an array. I commented the part which was wrong.
import java.util.Scanner;
public class SumOfPalindrome_1
{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of array elements");
int n = sc.nextInt();
int[] inp = new int[n];
System.out.println("enter the elements");
for(int i = 0; i< n ;i++)
{
inp[i] = sc.nextInt();
}
//System.out.println(SumOfPalindromeNumber(inp));
SumOfPalindromeNumber(inp);
}
private static void SumOfPalindromeNumber(int[] inp )
{
int sumpal =0;
for(int i = 0; i<inp.length;i++)
{
int rem =0;
int sum = 0;
while(inp[i]!=0)
{
rem = inp[i]%10;
sum=(sum*10)+rem;
inp[i]/=10;
}
if(inp[i]==sum)
{
// sumpal+=inp[i];
/*if(sumpal>9)
{
sumpal=singledigitsum(sumpal);
}
*/
System.out.println(singleDigitSum(inp[i]));
}
}
}
private static int singleDigitSum(int sumpal)
{
int rem1 = 0;
int sum1 = 0;
while(sumpal!=0)
{
rem1=sumpal%10;
sum1+=rem1;
sumpal/=10;
}
if(sum1>9)
{
sum1=singleDigitSum(sum1);
}
return sum1;
}
}
Apologies if this is not the case but this seems like you are looking for answers to a coding test.
Trying Code as follows But it not working as per requirement printing 0 if armstrong number and 1 if not armstrong number
Suggest correction for implementing this program
import java.util.Scanner;
class Example {
public static boolean solution(int N) {
boolean isNumber = false;
#SuppressWarnings("unused")
int i=1;
int c=0,a,temp;
temp=N;
while(N>0) {
a=N%10;
N=N/10;
c=c+(a*a*a);
}
if(temp==c) {
i = isNumber ? 1 : 0;
}
System.out.println(isNumber);
return isNumber;
}
}
class Arm {
public static void main(String[] args) {
#SuppressWarnings("resource")
Scanner s = new Scanner(System.in);
int N = s.nextInt();
#SuppressWarnings("unused")
Example ex= new Example();
Example.solution(N);
}
}
#Sanjyukta you have not assigned isNumber=true if the number is armstrong, so everytime it will return false and 0 and It will not update the value of i and isNumber.
Below code will update the isNumber and i values.
if (temp == c) {
isNumber = true;
i = isNumber ? 0 : 1;
}
System.out.println(isNumber + "\t" + i);
Answer of my question: It is possible by using Ternary operator
public static void solution(int N)
{
int c=0,a,temp;
temp=N;
while(N>0)
{
a=N%10;
N=N/10;
c=c+(a*a*a);
}
if(temp == c)
{
boolean b = true;
c = (b) ? 1 : 0;
}
else
{
boolean b = false;
c = (b) ? 1 : 0;
}
System.out.println(c);
}
class Arm
{
public static void main(String[] args)
{
#SuppressWarnings("resource")
Scanner s = new Scanner(System.in);
int N = s.nextInt();
#SuppressWarnings("unused")
Example ex= new Example();
ex.solution(N);
}
}
I wrote this code but every time I try to show the output to the user by a System.out.print statement something goes wrong.
The purpose of the code is to check if the array is "palindromic".
import java.util.Scanner;
public class u {
public static void main(String[] args) {
int [] arr = {1,2,3,4,3,2,1};
int counter1 = 0,counter2 = arr.length-1;
int x = arr.length/2;
while (counter1 < x ) {
if (arr[counter1] == arr [counter2]){
counter1++;
counter2--;
} else {System.out.println(":("); break;}
}
System.out.println("Bingo!");
}}
If the problem is that the program always prints "Bingo!" it's because break only ends the while loop. And the "Bingo!" line is outside the while loop so it will still be called. You can avoid this by either change break to return. You can also use labels:
x: {
while(...) {
...
else break x;
}
System.out.println("Bingo!");
}
import java.util.Scanner;
public class u {
public static void main(String[] args) {
boolean d = false;
int [] arr = {2,9,3,4,4,3,9,2};
int counter1 = 0,counter2 = arr.length-1;
int x = arr.length/2;
while (counter1 < x ) {
d = false;
if (arr[counter1] == arr [counter2]){
counter1++;
counter2--;
d = true;
} else break;
}
if (d)
System.out.println("Bingo!");
else System.out.println(":(");
}}
Hi I am having trouble with Scanner to get user input two separate ArrayList. When I run this code I get an IndexOutOfBounds exception after entering the two arrays.
The code adds two binary numbers together using logic of a ripple adder. An example of intended user input would be
Enter A array: 1 0 1 0
Enter B Array: 0 0 0 1
producing: 1 0 1 1
The code works when arrays are hard coded, how can I get the user to enter the arrays?
Code is shown below
import java.util.*;
public class AdderApp {
public static void main(String[] args) {
Scanner inputA = new Scanner(System.in);
ArrayList<Integer> aList = new ArrayList<Integer>();
ArrayList<Integer> bList = new ArrayList<Integer>();
int c = 0;
System.out.println("Enter A array");
aList.add(inputA.nextInt());
Scanner inputB = new Scanner(System.in);
System.out.println("Enter B array");
bList.add(inputB.nextInt());
Adder bit1 = new Adder(parseInput(aList.get(3)), parseInput(bList.get(3)), parseInput(c));
Adder bit2 = new Adder(parseInput(aList.get(2)), parseInput(bList.get(2)), bit1.getCout());
Adder bit3 = new Adder(parseInput(aList.get(1)), parseInput(bList.get(1)), bit2.getCout());
Adder bit4 = new Adder(parseInput(aList.get(0)), parseInput(bList.get(0)), bit3.getCout());
if (bit4.getCout() == false) {
System.out.println(bit4.toString() + " " + bit3.toString() + " " + bit2.toString() + " " + bit1.toString());
} else {
System.out.println("overflow!");
}
}
public static boolean parseInput(int i) {
if (i == 1) {
return true;
} else {
return false;
}
}
}
Code for Adder class:
public class Adder {
private boolean a, b, cin, cout, s;
/**
* Full Adder contructor
*/
public Adder(boolean a, boolean b, boolean cin) {
this.a = a;
this.b = b;
this.cin = cin;
s = nand(nand(a, b), cin); //sum bit
cout = or(and(nand(a, b), cin), and(a, b)); // - carry bit
}
/** Half adder constructor */
// public Adder (bloolean a, boolean b) {
//
// this.a = a;
// this.b = b;
//
// s =
//}
/**
* NAND gate
*/
public boolean nand(boolean a, boolean b) {
return a ^ b;
}
/**
* AND gate
*/
public boolean and(boolean a, boolean b) {
return a && b;
}
/**
* OR gate
*/
public boolean or(boolean a, boolean b) {
return a || b;
}
public boolean getCout() {
return cout;
}
public String toString() {
if (s == true) {
return "1";
} else {
return "0";
}
}
public String toStringCout() {
if (cout == true) {
return "1";
} else {
return "0";
}
}
}
Your entire AdderApp class can be simplified and improved to accept any bit length by accepting the input in a slightly different way and then using a for loop to add each bit. The parseInput function can be replaced with a simple boolean comparison:
import java.util.*;
public class AdderApp {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("Enter A array");
char[] aIn = input.nextLine().replace(" ", "").toCharArray();
System.out.println("Enter B array");
char[] bIn = input.nextLine().replace(" ", "").toCharArray();
StringBuilder result = new StringBuilder();
Adder bit = new Adder(false, false, false);
for (int i = aIn.length - 1; i >= 0; --i) {
bit = new Adder((aIn[i] == '1'), (bIn[i] == '1'), bit.getCout());
result.append(bit + " ");
}
System.out.println(bit.getCout() ? "overflow!" : result.reverse());
}
}
Scanner.nextInt gets the next integer in the input, and then stops. Each of your lists only contains 1 element.
Use something along these lines instead:
String[] input = inputA.nextLine().split(" ");
for (String s : input)
{
try { aList.add(Integer.parseInt(s)); }
catch(NumberFormatException nfe) { /* handle exception as desired */ }
}
Alternatively, you should be able to use something like:
while (inputA.hasNextInt())
{
aList.add(inputA.nextInt());
}
You should be having a for loop to have an input into your ArrayList.
System.out.println("Enter A array");
for (int i = 0; i < 4; i++) {
aList.add(inputA.nextInt());
}
Scanner inputB = new Scanner(System.in);
System.out.println("Enter B array");
for (int i = 0; i < 4; i++) {
bList.add(inputB.nextInt());
}
The user should input 4 numbers, your one just allow the user to enter 1 number:
int count = 0;
Scanner inputA = new Scanner(System.in);
System.out.println("Enter A array");
while(count < 4){
count++;
aList.add(inputA.nextInt());
}
count = 0;
Scanner inputB = new Scanner(System.in);
System.out.println("Enter B array");
while(count < 4){
count++;
bList.add(inputB.nextInt());
}
If you want to use hasNextInt():
while(inputA.hasNextInt()){
count ++;
aList.add(inputA.nextInt());
if(count == 4){
count = 0;
break;
}
}
I know it may be weird question but I'm really stuck. I have simple program with two classes. I need pass array from class A to class B. I did it but I cannot test it because I have no idea how to run program. When I click on the run then only one class started. I wanted test whole program and cannot find anything how to do it. Is there any command or something which say run class A and then class B? Without it I cannot test class B because values from Array (class A) are not loaded :/ Hope you understand what I mean.
I'm using eclipse.
Thanks!
Class MarkCalculator
import java.util.Scanner;
public class MarkCalculator {
public static int[] exam_grade = new int[6];
public static int[] coursework_grade = new int[6];
public static int[] coursework_weight = new int[2];
public static int[] module_points = new int[6];
public static String module_grade, holder;
public static int counter1 = 0, counter2 = 0;
public static void main(String[] args) {
Scanner input = new Scanner (System.in);
for (int i=0; i<3; i++){
System.out.printf(i+1+". Modelue"+" Enter grade of exam:");
while (!input.hasNextInt() ){
System.out.printf("Enter only numbers! Enter grade of your exam: ");
input.next();
}
exam_grade[i]=input.nextInt();
System.out.printf(i+1+". Modelue"+" Enter grade of coursework:");
while (!input.hasNextInt()){
System.out.printf("Enter only numbers! Enter grade of your coursework: ");
input.next();
}
coursework_grade[i]=input.nextInt();
}
computeMark(coursework_grade, exam_grade, module_points);
// calculate module grade
for(int i = 0 ;i < 3; i++){
if (module_points[i] < 35){
System.out.println(i+1+".Module: Fail");
}
else if (module_points[i] >= 35 && module_points[i] <= 40){
System.out.println(i+1+".Module: Pass by compensation");
counter1++;
}
else {
System.out.println(i+1+".Module: Pass");
counter2++;
}
}
holder = computeResult(module_points, counter1,counter2, module_grade);
System.out.println("Your stage result is: "+ holder);
input.close();
}
public static int[] computeMark (int coursework_grade[], int exam_grade[], int module_points[]){
coursework_weight[0]= 50;
coursework_weight[1]= 50;
for(int i=0;i<3;i++)
{
if (coursework_grade[i] < 35 || exam_grade[i] < 35){
module_points[i]=(coursework_grade[i]*coursework_weight[0] + (exam_grade[i]*(100-coursework_weight[1])))/100;
if (module_points[i] > 35){
module_points[i] = 35; }
else {
module_points[i] = 0;
}
}
else {
module_points[i]=((coursework_grade[i]*coursework_weight[0] + (exam_grade[i]*(100-coursework_weight[1])))/100); }
}
return module_points;
}
public static String computeResult (int module_points[], int counter1, int counter2, String module_grade ){
int sum = 0;
double average = 0;
for (int i = 0; i < 3; i++){
sum = sum + module_points[i];
average = sum / 3;
}
for (int i = 0; i < 3; i++){
if (counter2 == 3){
module_grade = "Pass";
}
else if (average >= 40 && counter1 <= 2) {
module_grade = "Pass by compensation";
}
else {
module_grade = "Fail";
}
}
return module_grade;
}
}
Class StudentChart
public class StudentChart {
public static void main(String[] args) {
for (int i = 0; i < 3; i++){
System.out.println(MarkCalculator.coursework_weight);
}
}
}
You only need one main method.
class A {
String s;
public A(String s){
this.s = s;
}
}
public class B {
public static void main(String[] args){
A a = new A("Hello");
System.out.println(a.s + " world!");
}
}
class B will be the application program, the one with the main method. It will get values from class A. class A does not need to run for class B app to work, even though it uses values from class A.
You can have a method with a different name in another class, and call that method from your main method.
Do not call it public static void main though - that should only be used for standalone programs. If the method requires some other code to be run prior to it, it should not be the main method of a Java program.