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

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