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How to find the min and max values with number of occurances for each

I'm having trouble solving this homework problem. The problem wants me to create a program that reads user input of numbers and get the minimum and maximum values of those numbers.
Basically, the output should be as follows:
Enter number count: 10
Enter 10 numbers separated by space and press ENTER: 1 2 3 1 2 3 4 5 6 3
Min is 1 and has 2 occurrences
Max is 6 and has 1 occurrences
I was able to create methods to get the min and max. I don't know how to get the number of occurrences for the min and max with what I have. I also don't know how to get the scanner to read an input of integers on the same line.
import java.util.Scanner;
public class homework2
{
public int min(int[] array)
{
int min = array[0];
for (int i = 0; i < array.length; i++)
{
if (array[i] < min)
{
min = array[i];
}
}
return min;
}
public int max(int[] array)
{
int max = 0;
for (int i = 0; i < array.length; i++)
{
if (array[i] > max)
{
max = array[i];
}
}
return max;
}
public static void main(String[] args)
{
Scanner s = new Scanner(System.in);
System.out.println("Enter the length of the array:");
int length = s.nextInt();
int[] myArray = new int[length];
System.out.println("Enter the elements of the array:");
for (int i = 0; i < length; i++)
{
myArray[i] = s.nextInt();
}
}
}

Here's a simple program to do what you need:
public static void main(String[] args) {
int[] array = {1, 2, 3, 1, 2, 3, 4, 5, 6, 3}; // get your actual array
int first = array[0];
// initial values
int min = first;
int minOccurs = 1;
int max = first;
int maxOccurs = 1;
for(int i = 1; i < array.length; i++) {
int current = array[i];
if(current == min) {
minOccurs++;
} else if (current < min) {
min = current;
minOccurs = 1;
}
if(current == max) {
maxOccurs++;
} else if (current > max) {
max = current;
maxOccurs = 1;
}
}
System.out.println("Min is " + min + " and has " + minOccurs + " occurrences");
System.out.println("Max is " + max + " and has " + maxOccurs + " occurrences");
// prints: "Min is 1 and has 2 occurrences"
// prints: "Max is 6 and has 1 occurrences"
}

One way is to store counts of each one of the numbers you see using a HashMap. The number itself can be the key and the value can be the count that you are incrementing.
You can also use a Math lib to output a min and max from the set of keys (numbers)
https://www.geeksforgeeks.org/java-math-min-method-examples/
https://www.geeksforgeeks.org/count-occurrences-elements-list-java/
Good luck!

Once you know what the maximum is, just count how many times that occurs in the array.
However, as #Babyburger points out, you don't need an array to compute either the maximum or how many times it occurs.

Here is one way to parse a line of space separated integer numbers into int array:
int[] array = Arrays
.stream(scanner.nextLine().trim().split("\\s+"))
.mapToInt(Integer::parseInt)
.toArray();

This should work for you. Let me know if you have questions:
import java.util.Scanner;
public class homework2 {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
System.out.println("Enter the length of the array:");
int length = s.nextInt();
System.out.println("Enter the elements of the array:");
int[] numbers = new int[length];
for (int i = 0; i < length; i++) {
numbers[i] = Integer.parseInt(s.next());
}
// take first element as max and min
int max = numbers[0];
int min = numbers[0];
// max and min exists so occurs at least once
int maxOcc = 1;
int minOcc = 1;
// start from i = 1; because we assigned the first element before
for (int i = 1; i < length; i++) {
int number = numbers[i];
if (number > max) {
max = number;
// start counting again
maxOcc = 1;
} else if (number == max) {
maxOcc++;
}
if (number < min) {
min = number;
// start counting again
minOcc = 1;
} else if (number == min) {
minOcc++;
}
}
System.out.println("max: " + max);
System.out.println("maxOcc: " + maxOcc);
System.out.println("min: " + min);
System.out.println("minOcc: " + minOcc);
}
}

Here is a solution to your problem. This takes a single string with numbers and spaces in-between, adds them to a dynamic array(ArrayList) and uses the min,max functions.
Do not initialize min and max=0 because we have to pick an integer from the provided list to start our comparison and that has to be the first element [0].
Code
import java.util.ArrayList;
import java.util.Scanner;
public class homework2 {
//Using static with functions because of the function calls in the Static
//main function
//Find the maximum number
public static int max(ArrayList<Integer> array) {
int max=array.get(0);
for(int i=0; i<array.size(); i++ ){
if(array.get(i)>max)
max = array.get(i);
}
return max;
}
//Calculate Maximum number's occurences
public static int maxOccur(int max,ArrayList<Integer> array){
int maxOccur=0;
for(int i=0; i<array.size(); i++ )
if(max==array.get(i)) maxOccur++;
return maxOccur;
}
//Find the minimum number
public static int min(ArrayList<Integer> array) {
int min=array.get(0);
for(int i=0; i<array.size(); i++ ){
if(array.get(i)<min)
min = array.get(i);
}
return min;
}
//Calculate Minimum number's occurences
public static int minOccur(int min,ArrayList<Integer> array){
int minOccur=0;
for(int i=0; i<array.size(); i++ )
if(min==array.get(i)) minOccur++;
return minOccur;
}
public static void main(String args[])
{
int minNum,maxNum;
Scanner in = new Scanner(System.in);
System.out.print("Enter the numbers separated by a space: ");
String number = in.nextLine();
//Separate the string by spaces in-between
String[] separatedNums = number.split(" ");
//Create a dynamic ArrayList to store any amount of integers
ArrayList<Integer> arrayList = new ArrayList<Integer>();
//Save the above string in the ArrayList after parsing into integer
for (String a : separatedNums)
arrayList.add(Integer.parseInt(a));
minNum=min(arrayList);
maxNum=max(arrayList);
//Output the results
System.out.println("Minimum Number="+minNum+" has
"+minOccur(minNum,arrayList)+" occurances");
System.out.println("Maximum Number="+maxNum+" has
"+maxOccur(maxNum,arrayList)+" occurances");
//Close the scanner
in.close();
}
}

I have to take integers in an array and output them in random order

This is the output i need (
Input Array: 1 2 3 4 5 6 7
Random Output: 7 2 3 6 1 5 4)
this is what i get
Input size of the Array
5
Input Value
1
Input Value
2
Input Value
3
Input Value
4
Input Value
5
Random Output: 2
Random Output: 0
Random Output: 0
Random Output: 0
Random Output: 0
The problem is with line 23 and im not sure how to fix it
import java.util.Random;
import java.util.Scanner;
public class problem_2 {
public static void main(String args[]){
Random r = new Random();
Scanner m = new Scanner(System.in);
System.out.println("Input size of the Array");
int size = m.nextInt();
int a[] = new int[size];
int b[] = new int[size];
for(int i = 0;i<a.length;i++) {
System.out.println("Input Value " +(i+1));
a[i] = m.nextInt();
}
int cell = 0;
int x = r.nextInt(size);
int value = a[x];
while(cell<size) {
for(int i =0; i<= size;i++) {
if (b[i]==value) {
cell++;
}
if(cell==0) {
b[cell] = value;
cell++;
}
System.out.println("Random Output: "+b[i]);
}
}
}
}

The problem is your code is going one too many indexes in the following for loop:
for(int i =0; i<= size;i++)
That's because you have to remember an array with say 5 elements has indexes 0-4. So while the size is the number of elements in the array the largest index is always (the number of elements) - 1.
So you should write the for loop like so:
for(int i = 0; i < size;i++)
Even then your code doesn't quite randomize correctly. The easiest way to randomize an array would be to swap out each element with another random element, like this:
//Randomize the array
for(int i = 0; i < size;i++) {
//lets get a random index in the array
int randIndex = (int)(Math.random()*size);
//then we will store the index we are swapping because its going to be overwritten
int temp = a[i];
//set our index equal to the random one
a[i] = a[randIndex];
//put our index's original value into the random index, so its not lost
a[randIndex] = temp;
}

thanks everyone for the help but i didnt learn any of the things in the others so
i found a easier way to do it
import java.util.Random;
import java.util.Scanner;
public class random{
public static void main(String args[]){
Random r = new Random();
Scanner m = new Scanner(System.in);
System.out.println("Input size of the Array");
int size = m.nextInt();
int a[] = new int[size];
int b[] = new int[size];
for(int i = 0;i<a.length;i++) {
System.out.println("Input Value ");
a[i] = m.nextInt();
}
int cell = 0;
while(cell<size) {
int n = r.nextInt(size);
int value = a[n];
int count = 0;
for(int i =0; i< size;i++) {
if (b[i]== value) {
count++;
}
}
if(count==0) {
b[cell] = value;
cell++;
}
}
System.out.println ("\n");
System.out.println("Input Array: ");
for (int i = 0; i<size; i++){
System.out.print(a[i] + " ");
}
System.out.println ("\n");
System.out.println("Random Output: ");
for (int i = 0; i<size; i++){
System.out.print(b[i] + " ");
}
}
}

Searching for a value in an array, and storing it if it doesn't exist

I am looking to input an integer between 10 and 100 into a one dimensional array, and if the value already exists anywhere in the array, do not insert it into the array, but notify user and resume input until 5 unique numbers are added.
Here is my code. I know it's not right, but you can see that what I am trying to do is use simple for loops and a search method to get the numbers, store them into the array and search for a duplicate. My problem in my code is that I can't seem to set the number I just entered as the variable 'key' which I need to send to the method 'search'.
// input an integer between 10 and 100, add to array and print results. if value is already in array, notify user, print array. keep adding to array until 5 unique values have been entered
import java.util.Scanner;
public class ArraySearch {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int[] list = new int[5];
for (int i = 0; i < list.length; i++) {
System.out.println("Enter number: ");
list[i] = input.nextInt();
}
int count = search(list, key);
System.out.println("It has been entered.");
}
public static int search(int[] list, int key) {
int count = 0;
for (int i = 0; i < list.length; i++) {
if (list[i].equals(key)) {
;
}
count++;
}
return (count);
}
}

Simple example with array. Could improve with alternate data structure list set.
The search() method is essentially included within the while() loop, namely the for() loop examples the search for a target number already being included.
int c = 0; is declared before the loops and makes sure to find 5 unique numbers.
import java.util.Arrays;
import java.util.Scanner;
public class ArraySearch {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
int[] list = new int[5];
int c = 0;
System.out.println("Enter number: ");
while (c < 5 && s.hasNext()) {
int n = s.nextInt();
boolean has = n >= 10 && n <= 100;
for (int i = 0; i <= c && !has; ++i)
if (list[i] == n)
has = true;
if (!has) {
System.out.println("It has been entered.");
list[c++] = n;
}
}
System.out.println("Result = " + Arrays.toString(list));
s.close();
}
}
Alternate version:
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;
public class ArraySearch {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
Set<Integer> set = new HashSet<Integer>(5);
int c = 0;
System.out.println("Enter number: ");
while (c < 5 && s.hasNext()) {
int n = s.nextInt();
if ((n < 10) || (n > 100) || !set.add(n))
continue;
else {
System.out.println("It has been entered.");
c++;
}
}
System.out.println("Result = " + set);
s.close();
}
}
additionally, using search()
public class App {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
int[] list = new int[5];
for (int i = 0; i < 5; i++) {
System.out.println("Enter number: ");
int n = s.nextInt();
if ((n >= 10 && n <= 100) && search(list, n) == 0) {
list[i] = n;
System.out.println("It has been entered.");
} else
i--;
}
System.out.println("Result = " + Arrays.toString(list));
s.close();
}
public static int search(int[] list, int key) {
int count = 0;
for (int i = 0; i < list.length; i++) {
if (list[i] == key) {
count++;
}
}
return count;
}
}
Edit: also added the 10-100 spec
edit2: using your approach with search() method

You are saving the input directly in the array.
Save the input in a temporal variable which you'll pass to search. And based on result of search you add to the array or prompt for another input.
int[] list = new int[5];
for (int i = 0; i < list.length; i++) {
System.out.println("Enter number: ");
int temp = input.nextInt();
if(search(list,temp) == 0)
list[i] = temp;
}else{
System.out.println("It has been entered.");
i--;
}
}

Java scanner output array values and output after sort method [duplicate]

This question already has answers here:
Need Java array help using scanner class to output an average and sort method
(4 answers)
Closed 6 years ago.
I have other code that outputs values such as min, max and average. I don't see how to output values in sorted arrays that user inputs through scanner.
import java.util.Scanner;
public class Arrayassignment {
public static void main(String[] args) {
Scanner keyboard=new Scanner(System.in);
System.out.println("Enter an integer for array size.");
int number= keyboard.nextInt();
int array[]=new int[number];
System.out.println("Array size " + number + " initiated.\n");
System.out.println("Now enter the array integers.");
for (int index = 0; index < number; index++)
{
array[index]=keyboard.nextInt();
}
keyboard.close();
System.out.println ( "Sorting " );
sort(array);
}
public static void sort(int[] arg) {
int arrange;
for (int i = 0; i < arg.length - 1; i++)
for (int j = i + 1; j < arg.length; j++) {
if (arg[i] > arg[j]) {
arrange = arg[i];
arg[i] = arg[j];
arg[j] = arrange;
System.out.println( arrange);
}
}
}
}
}

The question is bit unclear. I think what you want is to output and print the sorted array.
import java.util.Scanner;
import java.util.Arrays;
public class Arrayassignment {
public static void main(String[] args) {
Scanner keyboard=new Scanner(System.in);
System.out.println("Enter an intiger for array size.");
int number= keyboard.nextInt();
int array[]=new int[number];
System.out.println("Array size " + number + " initiated.\n");
System.out.println("Now enter the array intigers.");
for (int index = 0; index < number; index++)
{
array[index]=keyboard.nextInt();
}
keyboard.close();
System.out.println ( "Sorting " );
//call the sort mthod and get the returned sorted array
int[] sortedArray=sort(array);
//printing the sorted array
System.out.println(Arrays.toString(sortedArray));
}
public static int[] sort(int[] arg) {
int arrange;
for (int i = 0; i < arg.length - 1; i++){
for (int j = i + 1; j < arg.length; j++) {
if (arg[i] > arg[j]) {
arrange = arg[i];
arg[i] = arg[j];
arg[j] = arrange;
}
}
}
//return the sorted array
return arg;
}
}

Taking User Input for an Array

A link to the assignment:
http://i.imgur.com/fc86hG9.png
I'm having a bit of trouble discerning how to take a series of numbers and apply them to an array without a loop. Not only that, but I'm having a bit of trouble comparing them. What I have written so far is:
import java.util.Scanner;
public class Lottery {
public static void main(String[] args) {
int userInputs[] = new int[5];
int lotteryNumbers [] = new int[5];
int matchedNumbers =0;
char repeatLottery = '\0';
Scanner in = new Scanner (System.in);
do{
System.out.println("Enter your 5 single-digit lottery numbers.\n (Use the spacebar to separate digits): ");
for(int i = 0; i <5; i++ )
userInputs[i] = in.nextInt();
System.out.println("Your inputs: ");
printArray(userInputs);
System.out.println("\nLottery Numbers: ");
readIn(lotteryNumbers);
for(int i=0; i<5; i++) {
System.out.print(lotteryNumbers[i] + " ");
}
matchedNumbers = compareArr(userInputs, lotteryNumbers);
System.out.println("\n\nYou matched " + matchedNumbers + " numbers");
System.out.println("\nDo you wish to play again?(Enter Y or N): ");
repeatLottery = in.next().charAt(0);
}
while (repeatLottery == 'Y' || repeatLottery == 'y');
}
public static void printArray(int arr[]){
int n = arr.length;
for (int i = 0; i < n; i++) {
System.out.print(arr[i] + " ");
}
}
public static void readIn(int[] List) {
for(int j=0; j<List.length; j++) {
List[j] = (int) (Math.random()*10);
}
}
public static int compareArr (int[] list1, int[] list2) {
int same = 0;
for (int i = 0; i <= list1.length-1; i++) {
for(int j = 0; j <= list2.length-1; j++) {
if (list1[i] == list2[j]) {
same++;
}
}
}
return same;
}
}
As you'll notice, I commented out the input line because I'm not quite sure how to handle it. If I have them in an array, I should be able to compare them fairly easily I think. This is our first assignment handling arrays, and I think it seems a bit in-depth for only having one class-period on it; So, please forgive my ignorance. :P
Edit:
I added a new method at the end to compare the digits, but the problem is it compares them in-general and not from position to position. That seems to be the major issue now.

your question isn't 100% clear but i will try my best.
1- i don't see any problems with reading input from user
int[] userInput = new int[5]; // maybe here you had a mistake
int[] lotterryArray = new int[5]; // and here you were declaring your arrays in a wrong way
Scanner scanner = new Scanner(system.in);
for ( int i = 0 ; i < 5 ; i++)
{
userInput[i] = scanner.nextInt();
} // this will populate your array try to print it to make sure
Edit : important in the link you shared about the assignment the compare need to check the value and location so if there are two 5 one in input one in loterry array they need to be in the same location check the assignment again
// to compare
int result = 0 ; // this will be the number of matched digits
for ( int i = 0 ; i < 5 ; i++)
{
if ( userInput[i] == loterryArray[i] )
result++
}
// in this comparsion if the digits are equale in value and location result will be incremented