CCF_201409-1_相邻数对

#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;

int main()
{
    int n,a[1005];
    cin >> n;
    for(int i = 1;i <= n;i++)   cin >> a[i];
    sort(a+1,a+n+1);
    int num = 0;
    for(int i = 1;i < n;i++)
    {
        if(a[i+1]-a[i] == 1)    num++;
    }
    cout << num << endl;
    return 0;
}