201409-1 相邻数对 Java

import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int a[] = new int[n];
        for(int i=0;i<n;i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        int count = 0;
        for(int j=1;j<n;j++) {
            if(a[j]-a[j-1] == 1) {
                count++;
            }
        }
        sc.close();
        System.out.println(count);
    }
}