Print occurrence of integer in java
Solution: There will be many ways to solve this problem, but here we are giving two solutions to print occurrence of integer 1) Printing occurrence of integer using Collections.freequence() method 2) Printing occurrence of integer using HashMap
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import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.List; public class OccurrenceOfIntger { public static void main(String[] args) { List<Integer> c = new ArrayList<Integer>(); c.add(1); c.add(1); c.add(3); c.add(4); c.add(5); c.add(5); c.add(5); c.add(5); //print occurrence using Collections.freequency() method printOccurrence(c); //print occurrence using HashMap printOccurrenceUsingHashMap(c); } private static void printOccurrence(List<Integer> c) { for(Integer number : c){ System.out.println(number +" : " + Collections.frequency(c, number) ); } } private static void printOccurrenceUsingHashMap(List<Integer> c) { HashMap<Integer,Integer> map =new HashMap<Integer,Integer>(); for(Integer number:c){ if(map.get(number)==null) map.put(number, 1); else map.put(number, map.get(number) + 1 ); } System.out.println(map); } } |
Output
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1 : 2 1 : 2 3 : 1 4 : 1 5 : 4 5 : 4 5 : 4 5 : 4 {1=2, 3=1, 4=1, 5=4} |