Checked this out to find Missing number from arraylist:
import java.util.ArrayList;
import java.util.Random;
/*
* Code for missing number from arrayList whereNumbers added randomly
public class MissingNumber {
public static void main(String[] args) {
// declare an ArrayList to hold the random numbers
ArrayList<Integer> myArraylist = new ArrayList<>();
// declare an ArrayList to hold the missing numbers
ArrayList<Integer> missingNumbers = new ArrayList<>();
int maxRanNumb = 10;// random numbers will be 0-9
int size = 20; // size of myArrayList
for (int j = 0; j < size; j++) {
// Generate random numbers
Random rand = new Random();
int randomNumber = rand.nextInt(maxRanNumb);
// Put random numbers into myArrayList
myArraylist.add(randomNumber);
}
// Print myArrayList
System.out.println("Contents of myArraylist: " + myArraylist);
// Search missing number
for (int j = 0; j < maxRanNumb; j++)
if (!myArraylist.contains(j)) {
// Put missing numbers into missingNumbers
missingNumbers.add(j);
}
// Print missingNumbers
System.out.println("Missing numbers is : " + missingNumbers);
}
}
This will help you out!