Code c++ giúp e với ạ !

#include <iostream>
using namespace std;
int main() {
unsigned long long n;
cin>>n;
long long t;
if (n%2==0) {
t=n/2;
} else {
t=-((n+1)/2);
}
cout<<t<<endl;
return 0;
}

#include <bits/stdc++.h>
using namespace std;
unsigned long long int a;
int main() 
{
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    cin >> a;
    if(a % 2 == 0) cout << a / 2;
    else cout << -((a-1)/2);
    return 0;
}

$#khanhtaon$