问在输入用户的值后，如何使程序停止？

EN

import java.util.Scanner;
public class P1 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.println("Please enter the number of sides:");
        int s = input.nextInt();
        while ( s!=-1)
        {
            switch (s)
            {
            case 1: System.out.println("Line");
                break;
            case 2:System.out.println("Angle");
                break;
            case 3:System.out.println("Triangle");
                break;
            case 4:System.out.println("Quadrilateral");
                break;
            case 5:System.out.println("Pentagon ");
                break;
            case 6:System.out.println("Hexagon");
                break;
            case 7:System.out.println("Heptagon");
                break;
            case 8:System.out.println("Octagon");
                break;
            case 9:System.out.println("Nonagon");
                break;
            case 10:System.out.println("Decagon");
                break;
            default: System.out.println("Enter a valid value:");
            }   
        }
    }
}