I am trying to create a module that counts how many times each digits shows up in a given number. The issue I am having is that instead of adding 1 to the array value of the corresponding digit it seems to add 10, that or it concatenates the array's default value ( 0 in this case) although that seems very unlikely.
My module:
public class UtilNumber{
public static int [] Occurence(int nb){
int temp;
int [] t = new int [10];
while (nb !=0){
temp = nb % 10;
for (int i = 0; i < t.length ; i++){
t[temp]++;
}
nb /= 10;
}
return t;
}
}
My main:
import java.util.scanner;
public class Primary{
public static void main(String [] args){
Scanner keyboard = new Scanner(System.in);
int [] tab;
int nb = keyboard.nextInt();
tab = UtilNumber.Occurence(nb);
for (int i = 0 ; i < tab.length ; i++){
if (tab[i] != 0){
System.out.println(i+" is present "+tab[i]+" time(s).");
}
}
}
}
For example when I enter 888 it should return 3, but instead it returns 30.
It looks like instead of
for (int i = 0; i < t.length ; i++){
t[temp]++;
}
you should just do
t[temp]++;
Or you can write.
public static int [] occurence(long nb){
int[] count = new int [10];
for(;nb > 0;nb /= 10)
count[nb % 10]++;
return count;
}
Related
I got some problem someone of with really helped me but I got program source code who print all of divisor from array, but I tried to print a number with most divisor for ex. array[1,2,3,4,5] and I want to print that the number with most divisor is 4 (1,2,4)
public static class Main {
public static void main(String[] args) {
System.out.println(getNumWithMaxDivisors(numbers));
}
static int getNumDivisors(int n) {
int noOfDivisors = 0;
for (int i = 1; i <= n / 2; i++) {
if (n % i == 0) {
System.out.print(i + " ");
noOfDivisors++;
}
}
return noOfDivisors;
}
static int getNumWithMaxDivisors(int[] numbers) {
int currentMaxDivisors = 0;
int numWithMaxDivisors = numbers[0];
for (int i = 0; i < numbers.length; i++) {
int numDivisors = getNumDivisors(numbers[i]);
if (numDivisors > currentMaxDivisors) {
numWithMaxDivisors = numbers[i];
}
}
return numWithMaxDivisors;
}
}
Code looks that, do you know where is a problem ?
The problem is that inside of your getNumWithMaxDivisors() method, you are not redefining the current number of max divisors. To fix this, you can update it inside of the if statement as so:
static int getNumWithMaxDivisors(int[] numbers) {
int currentMaxDivisors = 0;
int numWithMaxDivisors = numbers[0];
for (int i = 0; i < numbers.length; i++) {
int numDivisors = getNumDivisors(numbers[i]);
if (numDivisors > currentMaxDivisors) {
currentMaxDivisors = numDivisors; //ADD THIS LINE
numWithMaxDivisors = numbers[i];
}
}
return numWithMaxDivisors;
}
Input:
int[] numbers = {1,2,3,4,5};
System.out.println(getNumWithMaxDivisors(numbers));
Output:
4
Side Note: You could just as well start your for loop at i = 2 in your getNumDivisors() method, since every number is divisible by 1, so there is no point in checking it. This just saves you a bit of time!
add this line of code currentMaxDivisors = numDivisors; inside your if-statement like so:
static int getNumWithMaxDivisors(int[] numbers) {
int currentMaxDivisors = 0;
int numWithMaxDivisors = numbers[0];
for (int i = 0; i < numbers.length; i++) {
int numDivisors = getNumDivisors(numbers[i]);
if (numDivisors > currentMaxDivisors) {
currentMaxDivisors = numDivisors; //here this is missing
numWithMaxDivisors = numbers[i];
}
}
return numWithMaxDivisors;
}
How to use multiple methods in a code? First it asks for the size of an array, then for the numbers of the element. One method is rounding numbers with a special rule.
Second method is a void method which modifies the array. Third method is making a new array with the modified values and returns to this array.
package tombtombbekerekit;
import java.util.Scanner;
public class TombTombbeKerekit {
public static int round(int osszeg)
{
int last_Digit = osszeg % 10;
if(last_Digit < 3)
return osszeg - last_Digit;
else if(last_Digit > 7)
return osszeg + (10 - last_Digit);
else
return osszeg - (last_Digit) + 5;
}
public static void roundSelf(int [] numbers)
{
int[] array = numbers;
for (int i = 0; i < array.length; i++)
return;
}
public static int [] roundNew(int [] numbers)
{
int [] newArray = new int[numbers.length];
return newArray;
}
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Kérem az összegek számát: ");
int size = sc.nextInt();
System.out.println("Kérem az összegeket: ");
int [] array = new int[size];
for (int i = 0; i < array.length; i ++)
{
array[i] = sc.nextInt();
}
int [] kerek = roundNew(array);
System.out.println("Kerekítve: ");
for (int i = 0; i < kerek.length; i++)
System.out.println(kerek[i]);
}
}
You should write your own function. Just find the rule for the rounding. You can use n%10 to get the last digit of an integer named n.
I've written something but haven't tested it, I believe it should work. Check it out:
public int weirdRounding(int n)
{
int last_Digit = n % 10;
if(last_Digit < 3)
return n - last_Digit;
else if(last_Digit > 7)
return n + (10 - last_Digit);
else // the last digit is 3,4,5,6,7
return n - (last_Digit) + 5;
}
Note: You should probably make this code more readable if you're going to use it. For example define int LOWER_BOUND = 3 and int UPPER_BOUND = 7 instead of using '3' and '7', you could also wrap the ugly expressions with functions (e.g. roundUp, roundToFive ..). #Magic_Numbers_Are_Bad
I was trying to solve the Maximum Integer Value problem form Geeksforgeeks.
The problem states the following:
Given a string S of digits(0-9), your task is to find the maximum value that can be obtained from the string by putting either '*' or '+' operators in between the digits while traversing from left to right of the string and picking up a single digit at a time.
Input:
The first line of input contains T denoting the number of testcases. T testcases follow. Each testcase contains one line of input denoting the string.
Output:
For each testcase, print the maximum value obtained.
this is what I did:
class GFG
{
public static void sort(int[] numbers)
{
int n = numbers.length;
for (int i = 1; i < n; ++i)
{
int key = numbers[i];
int j = i - 1;
while (j >= 0 && numbers[j] > key)
{
numbers[j + 1] = numbers[j];
j = j -1 ;
}
numbers[j + 1] = key;
}
System.out.println(numbers.length - 1);
}
public static void main (String[] args)
{
Scanner sc = new Scanner(System.in);
int testCases = sc.nextInt();
int [] maxNum;
for(int i = 0; i< testCases; i++)
{
String numbers = sc.nextLine();
char[] cNumbers = numbers.toCharArray();
maxNum = new int [cNumbers.length];
for(int j = 0; j + 1 < cNumbers.length; j++)
{
int sum = 0;
int mult = 0;
sum = cNumbers[j] + cNumbers[j + 1];
mult = cNumbers[j] * cNumbers[j + 1];
int maxNumber = Math.max(sum, mult);
maxNum[i] = maxNumber;
}
sort(maxNum);
}
}
}
an example of Input:
2
01230
891
My Output:
-1
4
Correct Output:
9
73
What is wrong with my code?!
Just quick glance it would seem if your digit is less than two it should be added. 2 or larger should get multiplied. Not at a PC to test though.
The idea is to put the operators alternatively and choose the maximum results.
import java.util.Scanner;
public class Demo {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int testCases = Integer.parseInt(sc.nextLine());
for (int i = 0; i < testCases; i++) {
String numbers = sc.nextLine();
int max = 0;
for (int j = 0; j + 1 < numbers.length(); j++) {
int next = Integer.parseInt(numbers.substring(j, j+1));
if (max + next > max * next)
max = max + next;
else
max = max * next;
}
System.out.println(max);
}
sc.close();
}
}
After the execution of
int testCases = sc.nextInt();
the buffer contains a new line character. So when executing the line
String numbers = sc.nextLine();
it read '\n' into numbers, so you got -1 as the first output.
Also you need to convert character to Integer before using it any arithmetic operations.
sum = cNumbers[j] + cNumbers[j+1];
mult = cNumbers[j] * cNumbers[j+1];
So the above code will give you wrong results.
I tried the following sample and worked.
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String inputAsString = sc.nextLine();
int testCases = Integer.parseInt(inputAsString);
int maxNumber = 0;
for (int i = 0; i < testCases; i++) {
String numbers = sc.nextLine();
if(!numbers.matches("\\d+")){
System.out.println("Only numeric values are expected.");
continue;
}
char[] cNumbers = numbers.toCharArray();
int sum = 0;
int mult = 1;
for (int j = 0; j < cNumbers.length; j++) {
int nextNumber = Character.getNumericValue(cNumbers[j]);
sum = sum + nextNumber;
mult = mult * nextNumber;
maxNumber = mult > sum ? mult : sum;
sum = maxNumber;
mult = maxNumber;
}
System.out.println(maxNumber);
}
sc.close();
}
I read your description and what you do is wrong. please read question carefully specially the example in reference site.
as mentioned in comments by moilejter you use sc.nextInt() which doesn't read '\n' and make problem. the next sc.nextLine() will read only a empty string and your program throw exception.
Second problem is that you must calculate max continuously and you don't need an int array (you calculate max result of operation between two successive number and save them in an array which is not correspond to max integer value. you only find max between each two digit but not max of operation on all digit).
Third problem is that you use character as numbers which is made incorrect result. (you must convert them to integer)
So there is a code that works for your output:
public class GFG
{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int testCases = Integer.valueOf(sc.nextLine());
for (int i = 0; i < testCases; i++)
{
String numbers = sc.nextLine();
char[] cNumbers = numbers.toCharArray();
long maxUntilNow = cNumbers[0] - '0';
for (int j = 1; j < cNumbers.length; j++)
{
int numberOfThisPlace = cNumbers[j] - '0';
maxUntilNow = Math.max(maxUntilNow + numberOfThisPlace,
maxUntilNow * numberOfThisPlace);
}
System.out.println(maxUntilNow);
}
}
}
I hope this is what you want.
As per the problem statement, we need to obtain maximum value from the string by putting either * or + operators in between the digits while traversing from left to right of the string and picking up a single digit at a time.
So, this can be solved in O(n) without using any sorting algorithm.
The simple logic behind the solution is whenever you find "0" or "1" in any of the operands use "+" and the rest of the places use "*".
Here is my solution which got successfully submitted:
import java.util.*;
import java.lang.*;
import java.io.*;
class GFG {
public static void main (String[] args) {
Scanner scan = new Scanner(System.in);
int T = Integer.parseInt(scan.nextLine());
while(T-- > 0) {
String str = scan.nextLine();
maxValue(str);
}
}
static void maxValue(String str) {
long maxNumber = 0;
for(int i = 0; i < str.length(); i++) {
int n = Character.getNumericValue(str.charAt(i));
if (maxNumber == 0 || maxNumber == 1 ||
n == 0 || n == 1) {
maxNumber += n;
} else {
maxNumber *= n;
}
}
System.out.println(maxNumber);
}
}
I have to make a 3 way merge sort of an array. the array length is a in a power of 3, i.e. 3,9,27 etc. So I can use only one split function and not "left","mid","right".
Would like to get an answer how to repair it and why does not it work.
I have written the code, however don't know how to get it to work.
Here it is:
EDITED THE CODE, STILL DOES NOT WORK
public class Ex3 {
public static void main(String[] args) { //main function
Scanner in = new Scanner(System.in); //scanner
int size = in.nextInt();
int[] arr = new int[size];
for (int i = 0; i<arr.length; i++){
arr[i] = in.nextInt();
}
in.close();
arr = merge3sort (arr); //send to the function to merge
for (int i = 0; i<arr.length; i++){ //printer
System.out.print(arr[i]+ " ");
}
}
static int[] split(int[] m, int thirdNum) { //split function that splits to 3 arrays
int third[] = new int[m.length/3];
int third1[]=new int[m.length/3];
int third2[]=new int[m.length/3];
for(int i = 0; i<=m.length/3; i++)
third[i]=m[i];
for(int i=0; i<=m.length/3;i++)
third1[i]=m[i+thirdNum];
for(int i=0; i<=m.length/3;i++)
third2[i]=m[i+2*thirdNum];
return merge(third,third1,third2);
//return null;
}
static int minOf3(int[] a3) { //function that finds out how what is the index of the smallest number
int num0 = a3[0];
int num1 = a3[1];
int num2 = a3[2];
int idx = 0;
if(num0<num1 && num1<num2)
idx=0;
if(num1<num0 && num0<num2)
idx=1;
else
idx=2;
return idx;
}
static int[] merge(int[] th0, int[] th1, int[] th2) { //function that sorts the numbers between 3 arrays
int len0=th0.length;
int len1=th1.length;
int len2=th2.length;
int[] united = new int[len0+len1+len2];
int ind = 0; int i0=0; int i1=0; int i2=0;
while(i0<len0 && i1<len1 && i2<len2){
if(th0[i0]<th1[i1]){
if(th0[i0]<th2[i2]){
united[ind]=th0[i0];
i0=i0+1;
}//end inner if
else{
united[ind]=th2[i2];
i2=i2+1;
}//end inner else
}//end outer if
else{
united[ind]=th1[i1];
i1=i1+1;
}//end outer else
ind=ind+1;
}//end while
for (int i = i0; i < len0; i = i + 1) {
united[ind] = th0[i];
ind = ind + 1;
}
for (int i = i1; i < len1; i = i + 1) {
united[ind] = th1[i];
ind = ind + 1;
}for (int i = i2; i < len2; i = i + 1) {
united[ind] = th2[i];
ind = ind + 1;
}
return united;
}
static int[] merge3sort(int[] m) { //function that glues all together
if (m.length == 1) {
return m;
}
else{
return merge(merge3sort(split(m,m.length/3)),merge3sort(split(m,m.length/3)),merge3sort(split(m,m.length/3))); }
}
I get the following exception:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
at ololosh1.Ex3.split(Ex3.java:27)
at ololosh1.Ex3.merge3sort(Ex3.java:98)
at ololosh1.Ex3.main(Ex3.java:15)
Look at this part of your code:
for(int i = 0; i<=m.length/3; i++)
third[i]=m[i];
for(int i=0; i<=m.length/3;i++)
third1[i]=m[i+thirdNum];
for(int i=0; i<=m.length/3;i++)
third2[i]=m[i+2*thirdNum];
Arrays are indexed from 0 to length-1. Each third* array has length m.length/3. Therefore their index can only go up to m.length/3 - 1. Yet you are indexing up to and including m.length/3.
Once you get your application working correctly, you really should clean it up. There is a lot of redundancy. For example, you are using the expression m.length/3 multiple times in method split() but you are also passing that same value to it as an argument.
public class AssignmentChapter8
{
public static void main(String[] args)
{
int randomNumbers = new int[100];
int counter = 0;
while(counter < randomNumbers.length)
{
randomNumbers[counter] = (int)(Math.random() * 25);
counter++;
}
int oddNumbers[] = new int[100];
oddNumbers[] = getOddNumbers(randomNumbers);
int evenNumbers[] = new int[100];
evenNumbers[] = getEvenNumbers(randomNumbers);
System.out.println("The odd numbers are:");
for(int k = 0; k < oddNumbers.length; k++)
System.out.print("\t" + oddNumbers[k]);
System.out.println("The even numbers are:");
for(int l = 0; l < evenNumbers.length; l++)
System.out.print("\t" + evenNumbers[l]);
}
public static int getOddNumbers(int randomNumbers)
{
int oddNumbers[] = new int[100];
int counterA = 0;
int counterB = 0;
int counter = 0;
int placeholder;
while(counter < randomNumbers.length)
{
if(randomNumbers[counterA] % 2 > 0)
{
oddNumbers[counterB] = randomNumbers[counterA];
counterB++;
}
counterA++;
counter++;
}
return oddNumbers;
}
public static int getEvenNumbers(int randomNumbers)
{
int evenNumbers[] = new int[100];
int counterA = 0;
int counterB = 0;
int counter = 0;
int placeholder;
while(counter < randomNumbers.length)
{
if(randomNumbers[counterA] % 2 > 0)
{
evenNumbers[counterB] = randomNumbers[counterA];
counterB++;
}
counterA++;
counter++;
}
return evenNumbers;
}
}
I have been trying to execute a program to sort variables in arrays, but I keep getting a ';' expected error in the line after declaration of the array where the program is supposed to retrieve an array from a function. Any help would be appreciated.
This is bad syntax (which causes the ';' expected error ):
oddNumbers[] = getOddNumbers(randomNumbers);
The brackets are not needed. You can do this:
oddNumbers = getOddNumbers(randomNumbers);
Besides that, you have plenty of errors:
int randomNumbers[] = new int[100]; // you need the brackets
Your return value in the method declaration is wrong (you are returning an array, not an int):
public static int[] getEvenNumbers(int randomNumbers)
int oddNumbers[] = new int[100];
By initializing oddNumbers become an array. when you want to assign values,
oddNumbers={elements of array}
Both left and right hand side both should arrays.
May be you should use IDE for coding then it may help you to understand some issues like this.