题解 | #正则序列#简洁易懂，不用STL

#include<iostream>
using namespace std;
int main(){
    int n;
    cin >> n;
    int b[20001] = {0};
    for (int i = 0, num; i < n; i++) {
        cin >> num;
        b[num + 10000]++;
    }
    int ans = 0;
    for (int num = 0, j = 1; num < 20001 && j <= n; num++) {
        while (b[num]--) {
            ans += abs(j++ - num + 10000);
        }
    }
    cout << ans;
    return 0;
}