Language: C++

/#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
#define rep1(i,n) for(int i=1;i<=(n);i++)
#define all(x) (x).begin(),(x).end()
#define V vector
typedef V<int> vi;
typedef V<vi> vvi;
typedef long long ll;
typedef pair<int, int> P;
typedef tuple<int, int, int> T;
constexpr auto INF = INT_MAX >> 1;
constexpr auto LINF = 5000000000000000LL;
constexpr auto MOD = 1000000007;

int main() {

	int n;
	cin >> n;
	vi a(n), b(n);
	rep(i, n)cin >> a[i] >> b[i];

	sort(all(a));
	sort(all(b));

	if (n % 2)cout << b[(n - 1) / 2] - a[(n - 1) / 2] + 1 << endl;
	else cout << b[(n - 2) / 2] + b[n / 2] - a[(n - 2) / 2] - a[n / 2] + 1 << endl;

}

Compiler output:
a.cc:1:2: error: stray '#' in program
    1 | /#include <bits/stdc++.h>
      |  ^
a.cc:1:1: error: expected unqualified-id before '/' token
    1 | /#include <bits/stdc++.h>
      | ^
a.cc:6:11: error: 'vector' does not name a type
    6 | #define V vector
      |           ^~~~~~
a.cc:7:9: note: in expansion of macro 'V'
    7 | typedef V<int> vi;
      |         ^
a.cc:6:11: error: 'vector' does not name a type
    6 | #define V vector
      |           ^~~~~~
a.cc:8:9: note: in expansion of macro 'V'
    8 | typedef V<vi> vvi;
      |         ^
a.cc:10:9: error: 'pair' does not name a type
   10 | typedef pair<int, int> P;
      |         ^~~~
a.cc:11:9: error: 'tuple' does not name a type
   11 | typedef tuple<int, int, int> T;
      |         ^~~~~
a.cc:12:22: error: 'INT_MAX' was not declared in this scope
   12 | constexpr auto INF = INT_MAX >> 1;
      |                      ^~~~~~~
a.cc:1:1: note: 'INT_MAX' is defined in header '<climits>'; this is probably fixable by adding '#include <climits>'
  +++ |+#include <climits>
    1 | /#include <bits/stdc++.h>
a.cc: In function 'int main()':
a.cc:19:9: error: 'cin' was not declared in this scope
   19 |         cin >> n;
      |         ^~~
a.cc:20:9: error: 'vi' was not declared in this scope
   20 |         vi a(n), b(n);
      |         ^~
a.cc:21:25: error: 'a' was not declared in this scope
   21 |         rep(i, n)cin >> a[i] >> b[i];
      |                         ^
a.cc:21:33: error: 'b' was not declared in this scope
   21 |         rep(i, n)cin >> a[i] >> b[i];
      |                                 ^
a.cc:23:18: error: 'a' was not declared in this scope
   23 |         sort(all(a));
      |                  ^
a.cc:5:17: note: in definition of macro 'all'
    5 | #define all(x) (x).begin(),(x).end()
      |                 ^
a.cc:23:9: error: 'sort' was not declared in this scope; did you mean 'short'?
   23 |         sort(all(a));
      |         ^~~~
      |         short
a.cc:24:18: error: 'b' was not declared in this scope
   24 |         sort(all(b));
      |                  ^
a.cc:5:17: note: in definition of macro 'all'
    5 | #define all(x) (x).begin(),(x).end()
      |                 ^
a.cc:26:19: error: 'cout' was not declared in this scope
   26 |         if (n % 2)cout << b[(n - 1) / 2] - a[(n - 1) / 2] + 1 << endl;
      |                   ^~~~
a.cc:26:66: error: 'endl' was not declared in this scope
   26 |         if (n % 2)cout << b[(n - 1) / 2] - a[(n - 1) / 2] + 1 << endl;
      |                                                                  ^~~~
a.cc:27:14: error: 'cout' was not declared in this scope
   27 |         else cout << b[(n - 2) / 2] + b[n / 2] - a[(n - 2) / 2] - a[n / 2] + 1 << endl;
      |              ^~~~
a.cc:27:83: error: 'endl' was not declared in this scope
   27 |         else cout << b[(n - 2) / 2] + b[n / 2] - a[(n - 2) / 2] - a[n / 2] + 1 << endl;
      |                                                                                   ^~~~