Java: Get a key-value mapping associated with the greatest key and the least key in a map

Last update on May 23 2025 13:08:14 (UTC/GMT +8 hours)

8. Get Mapping with Greatest and Least Key

Write a Java program to get a key-value mapping associated with the greatest key and the least key in a map.

Sample Solution:-

Java Code:

import java.util.*;
import java.util.Map.Entry;  
public class Example8 {  
     public static void main(String args[]) {

  // Create a tree map
  TreeMap <String,String> tree_map1 = new TreeMap <String,String> ();

  // Put elements to the map 
  tree_map1.put("C1", "Red");
  tree_map1.put("C2", "Green");
  tree_map1.put("C3", "Black");
  tree_map1.put("C4", "White");

  System.out.println("Orginal TreeMap content: " + tree_map1);
  System.out.println("Greatest key: " + tree_map1.firstEntry());
  System.out.println("Least key: " + tree_map1.lastEntry());
 }
}

Sample Output:

Orginal TreeMap content: {C1=Red, C2=Green, C3=Black, C4=White}        
Greatest key: C1=Red                                                   
Least key: C4=White

For more Practice: Solve these Related Problems:

Write a Java program to retrieve the entry with the greatest key using lastEntry() and the entry with the smallest key using firstEntry().
Write a Java program to compare the first and last entries of a TreeMap and print the difference between their keys.
Write a Java program to update the value of the mapping with the greatest key and then print the updated TreeMap.
Write a Java program to remove the entry with the smallest key using pollFirstEntry() and then display the new first entry.

Go to:

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NEXT : Get First and Last Key in TreeMap.

Java Code Editor:

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