How to find the Element with Minimum Number of Occurrences in a List in Java - Step by Step Examples

How to find the Element with Minimum Number of Occurrences in a List in Java ?

Answer

To find the element with the minimum number of occurrences in a list in Java, you can use a HashMap to count the occurrences.

✐ Examples

1 Find Least Frequent Integer in List

In this example,

We import the necessary classes from java.util package.
We create a list named data with several integer elements.
We declare a HashMap to count the occurrences of each element.
We iterate through the list to populate the map with counts.
We find the element with the minimum count by iterating through the map.
Finally, we print the least common element to the console.

Java Program

import java.util.*;

public class Main {
    public static void main(String[] args) {
        List<Integer> data = Arrays.asList(1, 2, 2, 3, 3, 3, 4);
        Map<Integer, Integer> count = new HashMap<>();
        for (int num : data) {
            count.put(num, count.getOrDefault(num, 0) + 1);
        }
        int leastCommon = data.get(0);
        int minCount = Collections.min(count.values());
        for (Map.Entry<Integer, Integer> entry : count.entrySet()) {
            if (entry.getValue() == minCount) {
                leastCommon = entry.getKey();
                break;
            }
        }
        System.out.println("Element with the minimum occurrences is: " + leastCommon);
    }
}

Output

Element with the minimum occurrences is: 1

2 Find Least Frequent String in List

In this example,

We import the necessary classes from java.util package.
We create a list named words with several string elements.
We declare a HashMap to count the occurrences of each element.
We iterate through the list to populate the map with counts.
We find the element with the minimum count by iterating through the map.
Finally, we print the least common element to the console.

Java Program

import java.util.*;

public class Main {
    public static void main(String[] args) {
        List<String> words = Arrays.asList("apple", "banana", "apple", "orange", "banana", "apple");
        Map<String, Integer> count = new HashMap<>();
        for (String word : words) {
            count.put(word, count.getOrDefault(word, 0) + 1);
        }
        String leastCommon = words.get(0);
        int minCount = Collections.min(count.values());
        for (Map.Entry<String, Integer> entry : count.entrySet()) {
            if (entry.getValue() == minCount) {
                leastCommon = entry.getKey();
                break;
            }
        }
        System.out.println("Element with the minimum occurrences is: " + leastCommon);
    }
}

Output

Element with the minimum occurrences is: orange

Summary

In this tutorial, we learned How to find the Element with Minimum Number of Occurrences in a List in Java language with well detailed examples.

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How to find the Element with Minimum Number of Occurrences in a List in Java - Step by Step Examples

How to find the Element with Minimum Number of Occurrences in a List in Java ?

Answer

✐ Examples

1 Find Least Frequent Integer in List

Java Program

Output

2 Find Least Frequent String in List

Java Program

Output

Summary

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