Java Collection, TreeMap Exercises: Get the least key strictly greater than the given key

Java Collection, TreeMap Exercises: Exercise-15 with Solution

Write a Java program to get the least key strictly greater than the given key. Return null if there is no such key.

Sample Solution:-

Java Code:

import java.util.*;
import java.util.Map.Entry;  
public class Example15 {  
       public static void main(String args[]){  
    // Create a tree map
   TreeMap< Integer, String > tree_map1 = new TreeMap< Integer, String >();      
  // Put elements to the map 
  tree_map1.put(10, "Red");
  tree_map1.put(20, "Green");
  tree_map1.put(40, "Black");
  tree_map1.put(50, "White"); 
  tree_map1.put(60, "Pink"); 
      System.out.println("Orginal TreeMap content: "+tree_map1);
	  System.out.println("Checking the entry for 10: ");
      System.out.println("Key(s): "+tree_map1.higherEntry(10));  
	  System.out.println("Checking the entry for 20: ");
      System.out.println("Key(s): "+tree_map1.higherEntry(20));  
	  System.out.println("Checking the entry for 70: ");
      System.out.println("Key(s): "+tree_map1.higherEntry(70));  

Sample Output:

Orginal TreeMap content: {10=Red, 20=Green, 40=Black, 50=White, 60=Pink
Checking the entry for 10:                                             
Key(s): 20=Green                                                       
Checking the entry for 20:                                             
Key(s): 40=Black                                                       
Checking the entry for 70:                                             
Key(s): null

Java Code Editor:

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Java: Tips of the Day

Choice between Float and Double:

Data type Bytes used Significant figures (decimal)
Float 4 7
Double 8 15

Double is often preferred over float in software where precision is important because of the following reasons:
Most processors take nearly the same amount of processing time to perform operations on Float and Double. Double offers far more precision in the same amount of computation time.

Ref: https://bit.ly/3oj7K2K