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Java Collection, ArrayList Exercises: Swap two elements in an array list

Java Collection, ArrayList Exercises: Exercise-14 with Solution

Write a Java program of swap two elements in an array list.

Pictorial Presentation:

Java Collection, ArrayList Exercises: Swap two elements in an array list

Sample Solution:-

Java Code:

import java.util.ArrayList;
import java.util.Collections;
  public class Exercise14 {
  public static void main(String[] args) {
   ArrayList<String> c1= new ArrayList<String>();
          c1.add("Red");
          c1.add("Green");
          c1.add("Black");
          c1.add("White");
          c1.add("Pink");

          System.out.println("Array list before Swap:");
          for(String a: c1){
          System.out.println(a);
        }
          //Swapping 1st(index 0) element with the 3rd(index 2) element
         Collections.swap(c1, 0, 2);
          System.out.println("Array list after swap:");
          for(String b: c1){
          System.out.println(b);
         }
     }
}

Sample Output:

Array list before Swap:                                                
Red                                                                    
Green                                                                  
Black                                                                  
White                                                                  
Pink                                                                   
Array list after swap:                                                 
Black                                                                  
Green                                                                  
Red                                                                    
White                                                                  
Pink 

Flowchart:

Flowchart: Swap two elements in an array list.

Java Code Editor:

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Next: Join two array lists.

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getEnumMap

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