package misc; /** * Logic:- * loop through the given array and tick marking all the numbers * which are present by storing one of their respective indices. * */ public class MissingNumber_02 { public static void main(String[] args) { int[] input = { 1, 1, 2, 3, 5, 5, 7, 9, 9, 9 }; int[] register = new int[input.length]; for (int i : input) { register[i] = 1; } System.out.println("Missing number: "); for (int i = 1; i < register.length; i++) { if (register[i] == 0) { System.out.println(i); } } } }