I have tried the other questions like this but none seem to match it. I want it to repeat if the user enters Y after the numbers are sorted in the console.
Here is the code:
package compsorter;
import java.util.Scanner;
public class Ascending_Order
{
public static void main(String[] args)
{
int n, temp;
Scanner s = new Scanner(System.in);
System.out.print("Enter no. of elements you want in array:");
n = s.nextInt();
int a[] = new int[n];
System.out.println("Enter all the elements:");
for (int i = 0; i < n; i++)
{
a[i] = s.nextInt();
}
for (int i = 0; i < n; i++)
{
for (int j = i + 1; j < n; j++)
{
if (a[i] > a[j])
{
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
}
System.out.print("In Ascending Order:");
for (int i = 0; i < n - 1; i++)
{
System.out.print(a[i] + ",");
}
System.out.print(a[n - 1]);
s.close();
}
}
Thanks!
Like this,
do{
//code here
//take input from user 'Y' or 'N'
}while(condition);
try do while for this reason.here is example of that : link
You can put
do { after
Scanner s = new Scanner(System.in);
and
} while(s.readLine().equals("Y"))
before
s.close();
You can do it with while loop.
Below is main method program you should have.
public static void main(String[] args) {
String flag = "Y";
Scanner s = new Scanner(System.in);
while (true) {
if ("Y".equalsIgnoreCase(flag)) {
int n, temp;
System.out.print("Enter no. of elements you want in array:");
n = s.nextInt();
int a[] = new int[n];
System.out.println("Enter all the elements:");
for (int i = 0; i < n; i++) {
a[i] = s.nextInt();
}
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
if (a[i] > a[j]) {
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
}
System.out.print("In Ascending Order:");
for (int i = 0; i < n - 1; i++) {
System.out.print(a[i] + ",");
}
System.out.print(a[n - 1]);
System.out.println();
System.out.print("Do you want to continue Y/N?");
flag = s.next();
} else {
break;
}
}
s.close();
}
Related
import java.util.*;
public class Combination {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number : ");
String input = sc.next();
System.out.printf("You entered: %d\n", Integer.parseInt(input));
sc.close();
int[] arr = new int[100];
for (int i = 0; i < arr.length; i++) {
arr[i] = i + 1;
}
for (int i = 0; i <= 97; i++) {
int num_i = arr[i];
for (int j = i + 1; j <= 98; j++) {
int num_j = arr[j];
for (int k = j + 1; k <= 99; k++) {
int num_k = arr[k];
if (num_i + num_j + num_k == Integer.parseInt(input))
System.out.printf("(%d, %d, %d)", num_i, num_j, num_k);
}
}
}
}
}
When I get a number input, I want to make a code that represents this number as the sum of three numbers.
The code is complete, but there are several combinations. I want to print out only one combination. How can I edit it?
First, some important suggestions:
Do not parse input inside the nested loop as it will hit the performance. Do it once outside the nested loops.
Do not close Sacnner for System.in as it also closes System.in and there is no way to open it again without restarting JVM. It means that if it is being used in some other part of your application, your application will crash.
Always follow Java naming conventions e.g. you could name numJ instead of num_j.
Coming back to your problem, there are many ways to solve it and I have listed below just a couple of them:
Use break <<label>> to exit the nested loops:
import java.util.Scanner;
public class Combination {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number : ");
String input = sc.next();
System.out.printf("You entered: %d\n", Integer.parseInt(input));
int num = Integer.parseInt(input);
int[] arr = new int[100];
for (int i = 0; i < arr.length; i++) {
arr[i] = i + 1;
}
start: for (int i = 0; i <= 97; i++) {
int numI = arr[i];
for (int j = i + 1; j <= 98; j++) {
int numJ = arr[j];
for (int k = j + 1; k <= 99; k++) {
int numK = arr[k];
if (numI + numJ + numK == num) {
System.out.printf("(%d, %d, %d)", numI, numJ, numK);
break start;
}
}
}
}
}
}
A sample run:
Enter a number : 123
You entered: 123
(1, 22, 100)
Put the logic in a method and return:
import java.util.Scanner;
public class Combination {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number : ");
String input = sc.next();
System.out.printf("You entered: %d\n", Integer.parseInt(input));
int num = Integer.parseInt(input);
printFirstCombination(num);
}
static void printFirstCombination(int num) {
int[] arr = new int[100];
for (int i = 0; i < arr.length; i++) {
arr[i] = i + 1;
}
for (int i = 0; i <= 97; i++) {
int numI = arr[i];
for (int j = i + 1; j <= 98; j++) {
int numJ = arr[j];
for (int k = j + 1; k <= 99; k++) {
int numK = arr[k];
if (numI + numJ + numK == num) {
System.out.printf("(%d, %d, %d)", numI, numJ, numK);
return;
}
}
}
}
}
}
You can create a seperate function for that and after you find a combination, print it and return there and then to the main function. In case you didn't find a combination you return 1 which can be handled in the main function,
public class Combination {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number : ");
String input = sc.next();
System.out.printf("You entered: %d\n", Integer.parseInt(input));
int res = printCombination(input);
if(res == 1) {
// Do something
}
sc.close();
}
private static int printCombination(String input) {
int[] arr = new int[100];
for (int i = 0; i < arr.length; i++) {
arr[i] = i + 1;
}
for (int i = 0; i <= 97; i++) {
int num_i = arr[i];
for (int j = i + 1; j <= 98; j++) {
int num_j = arr[j];
for (int k = j + 1; k <= 99; k++) {
int num_k = arr[k];
if (num_i + num_j + num_k == Integer.parseInt(input)) {
System.out.printf("(%d, %d, %d)", num_i, num_j, num_k);
return 0;
}
}
}
}
return 1;
}
}
I have just started to do programming ...I am trying to sort an array in ascending order.. but not getting desired result , please point where i am doing wrong..
public static void main(String[] args) {
int count, temp;
// User inputs the array size
Scanner scan = new Scanner(System.in);
System.out.print("Enter number of elements you want in the array: ");
count = scan.nextInt();
int num[] = new int[count];
System.out.println("Enter array elements:");
for (int i = 0; i < count; i++) {
num[i] = scan.nextInt();
}
scan.close();
{
int i = 0;
while (i <= count) {
for (int j = i + 1; j < count; j++) {
if (num[i] > num[j]) {
temp = num[i];
num[i] = num[j];
num[j] = temp;
i++;
}
}
}
}
System.out.print("Array Elements in Ascending Order: ");
for (int i = 0; i < count - 1; i++) {
System.out.print(num[i] + ", ");
}
System.out.print(num[count - 1]);
}
you should increment the i outside the for loop or you can get rid of the while loop and use for loop too, you can find the code below :
import java.util.Scanner;
public class Ascending _Order
{
public static void main(String[] args)
{
int n, temp;
Scanner s = new Scanner(System.in);
System.out.print("Enter no. of elements you want in array:");
n = s.nextInt();
int a[] = new int[n];
System.out.println("Enter all the elements:");
for (int i = 0; i < n; i++)
{
a[i] = s.nextInt();
}
for (int i = 0; i < n; i++)
{
for (int j = i + 1; j < n; j++)
{
if (a[i] > a[j])
{
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
}
System.out.print("Ascending Order:");
for (int i = 0; i < n - 1; i++)
{
System.out.print(a[i] + ",");
}
System.out.print(a[n - 1]);
}
}
Output:
Enter no. of elements you want in array:5
Enter all the elements: 4 3 2 6 1
Ascending Order:1,2,3,4,6
or you can use the method sort :
import java.util.Scanner;
import java.util.Arrays;
public class Ascending_Order {
public static void main(String[] args) {
int n, temp;
Scanner s = new Scanner(System.in);
System.out.print("Enter no. of elements you want in array:");
n = s.nextInt();
int a[] = new int[n];
System.out.println("Enter all the elements:");
for (int i = 0; i < n; i++) {
a[i] = s.nextInt();
}
Arrays.sort(a);
System.out.print("Ascending Order:");
for (int i = 0; i < n - 1; i++) {
System.out.print(a[i] + ",");
}
System.out.print(a[n - 1]);
}
}
Output:
Enter no. of elements you want in array:5
Enter all the elements: 4 3 2 6 1
Ascending Order:1,2,3,4,6
I had an assignment for a class where I had to develop a simple number sort program.
My main is supposed to receive the user input and my sort class is supposed to interrupt and spit out the resulting numbers in ascending and descending order. The problem is that my main is taking the input but it's not putting it in order at all and I'm unsure why.
package main;
import sort.Sort;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
int arr[] = new int[5];
Scanner myScanner = new Scanner(System.in);
for(int i=0; i<5; i++) {
System.out.print("Enter a number: ");
myScanner.nextLine();
}
Sort sortObj = new Sort();
sortObj.ascendingsort(arr);
}
}
package sort;
public class Sort {
public void ascendingsort(int arr[])
{
int n = arr.length;
for (int i = 0; i < n-1; i++)
{
int min_idx = i;
for (int j = i+1; j < n; j++)
if (arr[j] < arr[min_idx])
min_idx = j;
int temp = arr[min_idx];
arr[min_idx] = arr[i];
arr[i] = temp;
}
}
void descendingsort(int arr[])
{
int n = arr.length;
for (int i = 0; i < n-1; i++)
{
int min_idx = i;
for (int j = i+1; j < n; j++)
if (arr[j] < arr[min_idx])
min_idx = j;
int temp = arr[min_idx];
arr[min_idx] = arr[i];
arr[i] = temp;
}
}
}
I know I'm missing something in my Main, because I'm fairly certain I don't need to put anything else into the sort class.
You're code is perfect. You just missed one assignment in your main method.
Instead of myScanner.nextLine(); you should have written arr[i] = myScanner.nextLine();
myScanner.nextLine(); is getting the next line you enter in the console but it isn't saving it anywhere. arr[i] = myScanner.nextLine(); will save the value of the console in the arr array.
Everything else should work after that.
First you are getting user input using myScanner.nextLine() but not storing it. myScanner.nextLine() won't save anything which user enters .
Thus you need to store it in an array and then use it later. So your main method after the changes should be like this.
public static void main(String[] args) {
int arr[] = new int[3];
Scanner myScanner = new Scanner(System.in);
for(int i=0; i<3; i++) {
System.out.print("Enter a number: ");
arr[i] = myScanner.nextInt();
}
Sort sortObj = new Sort();
sortObj.ascendingsort(arr);
}
And your sorting functions are also wrong. There you do some mis-calculations and return / log nothing. Thus you will not see anything in the console if you are not logging or returning anything.
public void descendingsort(int array[]) {
int n = array.length;
int i, j, temp;
for (i = 0; i < ( n- 1 ); i++) {
for (j = 0; j < n - i - 1; j++) {
if (array[j] < array[j+1])
{
temp = array[j];
array[j] = array[j+1];
array[j+1] = temp;
}
}
}
for (i = 0; i < n; i++){
System.out.println(array[i]);
}
}
public void ascendingsort(int array[]) {
int n = array.length;
int i, j, temp;
for (i = 0; i < ( n- 1 ); i++) {
for (j = 0; j < n - i - 1; j++) {
if (array[j] > array[j+1])
{
temp = array[j];
array[j] = array[j+1];
array[j+1] = temp;
}
}
}
for (i = 0; i < n; i++){
System.out.println(array[i]);
}
}
I hope this functions will work for your use case of ascending and descending sort.
This question already has answers here:
How do I create a file and write to it?
(35 answers)
Closed 4 years ago.
I'm writing code that prints you combination of numbers from 1 to n. In console it works perfectly fine, but i need to print it into file.
What should i do?
Code:
public class Permutace {
public static void main(String args[]){
Scanner sc = new Scanner(System.in);
System.out.println("your number: ");
int N = sc.nextInt();
int[] sequence = new int[N];
for (int i = 0; i < N; i++) {
sequence[i] = i + 1;
}
permute(sequence, 0);
}
public static void permute(int[] a, int k){
if (k == a.length) {
for (int i = 0; i < a.length; i++) {
System.out.print(a[i]);
}
System.out.println();
} else {
for (int i = k; i < a.length; i++) {
int temp = a[k];
a[k] = a[i];
a[i] = temp;
permute(a, k + 1);
temp = a[k];
a[k] = a[i];
a[i] = temp;
}
}
}
}
public static void main(String args[]){
Scanner sc = new Scanner(System.in);
System.out.println("your number: ");
int N = sc.nextInt();
int[] sequence = new int[N];
PrintWriter writer = new PrintWriter("the-file-name.txt", "UTF-8");
for (int i = 0; i < N; i++) {
sequence[i] = i + 1;
}
permute(sequence, 0);
writer.close();
}
public static void permute(int[] a, int k){
if (k == a.length) {
for (int i = 0; i < a.length; i++) {
writer.println(a[i]);
}
writer.println();
} else {
for (int i = k; i < a.length; i++) {
int temp = a[k];
a[k] = a[i];
a[i] = temp;
permute(a, k + 1);
temp = a[k];
a[k] = a[i];
a[i] = temp;
}
}
}
The code is supposed to output sorted array, yet it outputs zeros.
As an example, when running the program, write "2" when it asks for method, then "5", when it asks for count and "10" "9" "2" "5" "0", when it's asking for items. Then you'll see. I followed all the instructions given and I can't seem to find the problem with code, which changes inputted numbers to zeros, when outputting...
public static void secondMethod(int[] a) {
long t1 = System.nanoTime();
int N = a.length;
int b[] = new int[N];
int c[] = new int[N];
int[] tmp;
int len = 1;
for (int i = 0; i < a.length; i++) {
a[i] = b[i];
}
while (len < N) {
int n = 0;
int i;
int j;
int ri;
int rj;
for (int k=0; k<b.length; k+=2*len){{
n=k;
i = k;
j = k+len;
if(k+len<N){
ri = k+len;
}else{
ri = N;
}
if(k+2*len<N){
rj = k+2*len;
}else{
rj = N;
}
}
while(i<ri && j<rj){
if(b[i]<b[j]){
c[n]=b[i];
i++;
n++;
}else{
c[n]=b[j];
j++;
n++;
}
}
while(i<ri){
c[n]=b[i];
i++;
n++;
}
while(j<rj){
c[n]=b[j];
j++;
n++;
}
}
len = len*2;
tmp = b;
b = c;
c = tmp;
}
for (int i = 0; i < a.length; i++) {
a[i] = b[i];
}
long t2 = System.nanoTime();
long t = t2 - t1;
System.out.println("t=" + t);
}
public static void main(String[] args) {
int nm, mtd;
Scanner sc = new Scanner(System.in);
System.out.print("method: ");
if (sc.hasNextInt())
mtd = sc.nextInt();
else {
System.out.println("input-output error");
sc.close();
return;
}
if (mtd != 1 && mtd != 2) {
System.out.println("input-output error");
sc.close();
return;
}
System.out.print("count: ");
if (sc.hasNextInt())
nm = sc.nextInt();
else {
System.out.println("input-output error");
sc.close();
return;
}
int a[] = new int[nm];
System.out.println("items: ");
for (int i = 0; i < a.length; i++) {
if (sc.hasNextInt())
a[i] = sc.nextInt();
else {
System.out.println("input-output error");
sc.close();
return;
}
}
sc.close();
if (mtd == 1) {
firstMethod(a);
System.out.println("sorted: ");
for (int i = 0; i < a.length; i++)
System.out.print(a[i] + " ");
}
if (mtd == 2){
secondMethod(a);
System.out.println("sorted: ");
for (int i = 0; i < a.length; i++)
System.out.print(a[i] + " ");
}
}
In your code, in the secondMethod(int[] a) method, in the first for loop, use
b[i] = a[i];
instead of
a[i] = b[i];
and it should work.
Try debugging next time, it helps.