AreaPeri Error in java

general
1

import java.util.Scanner;

public class AreaPeri {
public static void main(String args[]){
int length;
int width;
Scanner sc = new Scanner(System.in);

width=sc.nextInt();
length=sc.nextInt();
int area=width*length;
int perimeter=2*(width+length);
  
if(perimeter>area){
    System.out.print("Perimeter :" );
    System.out.println(perimeter);
        }
    else{
    
    System.out.print("Area");
    System.out.println(area);
            }          
 }

}
/* I am uploading file or submitting this code showing below error this is my first question how to declare file name with extension java.

Main.java:3: error: class Collection is public, should be declared in a file named AreaPeri.java
public class AreaPeri {
^
1 error
*/

2

Finally I found answer error due to file name must be Main. but after compilation answer is wrong. what is mistake here now.