codeforces 285C - Building Permutation

//CF 285C
//2013-06-06-19.57
#include <stdio.h>
#include <stdlib.h>
#include <algorithm>
using namespace std;
const int maxn = 3*100001;

int a[maxn];

int main()
{
    int n;
    while (scanf("%d", &n) != EOF)
    {
        for (int i = 0; i < n; i++)
            scanf("%d", &a[i]);
        sort(a, a+n);
        __int64 ans = 0;
        for (int i = 0; i < n; i++)
            ans += abs(i+1-a[i]);
        printf("%I64d\n", ans);
    }
    return 0;
}