func_code_string: #include <bits/stdc++.h>   using namespace std;   long long p = 998244353;   int gcd(int a, int b, int& x, int& y) {     if (a == 1) {       x = 1;       y = 0;       return 1;     }     if (b == 1) {       x = 0;       y = 1;       return 1;     }     if (b == 0) {       x = 1;       y = 0;       return a;     }     int res = gcd(b, a % b, y, x);     y = y - x * (a / b);     return res;   }   long long Denominator(long long a) {     int x = 0, y = 0;     if (a == 0) return 1;     gcd(p, a, x, y);     return (y + p) % p;   }   int main() {     long long n, res = 1;     cin >> n;     for (long long i = 1; i <= n; ++i) {       res *= (n + i);       res = res % p;       res *= Denominator(i);       res = res % p;     }     long long sum = 0;     vector<long long> a(2 * n);     for (int i = 0; i < 2 * n; ++i) {       cin >> a[i];     }     sort(a.begin(), a.end());     for (int i = 0; i < n; ++i) {       sum += a[2 * n - 1 - i] - a[i];     }     cout << res * (sum % p) % p << endl;     return 0;   }   