Language: C++

#include <bits/stdc++.h>
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define FORR(i,a,b) for (int i=(a);i>=(b);i--)
#define pb push_back
#define pcnt __builtin_popcount
#define show(x) cout<<#x<<" = "<<x<<endl;
#define maxs(x,y) x = max(x,y)
#define mins(x,y) x = min(x,y)
#define fi first
#define se second
#define rng(a) (a.begin()),(a.end())
#define each(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define sz(x) (int)(x).size()
#define mp make_pair

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vpii;
typedef set<int> si;
typedef pair<ll,ll> pll;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pll> vpll;
typedef set<ll> sl;
typedef __int128_t lll;
typedef pair<lll,lll> plll;
typedef vector<lll> vlll;
template<typename T>string join(vector<T>&v)
{stringstream s;FOR(i,0,sz(v))s<<' '<<v[i];return s.str().substr(1);}
template<typename A, size_t N, typename T>void Fill(A (&array)[N], const T&v)
{fill((T*)array,(T*)(array+N),v);}
ll gcd(ll a,ll b){if(a>b)swap(a,b);for(;a>0;b%=a,swap(a,b));return b;}
int modpow(ll a,ll n,int m){if(a==0)return a;ll p=1;for(;n>0;n/=2,a=a*a%m)if(n&1)p=p*a%m;return(int)p;}
void dout(double d){printf("%.12f\n",d);}

const int iinf = 1e9;
const ll linf = 1e18;
const int mod = 1e9+7;
const double pi = acos(-1);
const double eps = 1e-10;
int n;
main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> n;
  vector<bool> b(2002001);
  b[0] = true;
  int s = 0;
  FOR(i, 0, n){
    int a;
    cin >> a;
    s += a;
    FORR(j, min(s, 2002000), a) b[j] |= b[j-a];
  }
  FOR(i, (s+1)/2, s+1) if(b[i]){
    cout << i << endl;
    break;
  }
  return 0;
}


Compiler output:
a.cc:45:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   45 | main(){
      | ^~~~
a.cc: In function 'int main()':
a.cc:56:38: error: no match for 'operator|=' (operand types are 'std::vector<bool>::reference' and 'std::vector<bool>::reference')
   56 |     FORR(j, min(s, 2002000), a) b[j] |= b[j-a];
      |                                 ~~~~~^~~~~~~~~
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:41,
                 from a.cc:1:
/usr/include/c++/14/cstddef:168:3: note: candidate: 'constexpr std::byte& std::operator|=(byte&, byte)'
  168 |   operator|=(byte& __l, byte __r) noexcept
      |   ^~~~~~~~
/usr/include/c++/14/cstddef:168:20: note:   no known conversion for argument 1 from 'std::vector<bool>::reference' to 'std::byte&'
  168 |   operator|=(byte& __l, byte __r) noexcept
      |              ~~~~~~^~~
In file included from /usr/include/c++/14/streambuf:43,
                 from /usr/include/c++/14/bits/streambuf_iterator.h:35,
                 from /usr/include/c++/14/iterator:66,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:54:
/usr/include/c++/14/bits/ios_base.h:104:3: note: candidate: 'constexpr const std::_Ios_Fmtflags& std::operator|=(_Ios_Fmtflags&, _Ios_Fmtflags)'
  104 |   operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b) _GLIBCXX_NOTHROW
      |   ^~~~~~~~
/usr/include/c++/14/bits/ios_base.h:104:29: note:   no known conversion for argument 1 from 'std::vector<bool>::reference' to 'std::_Ios_Fmtflags&'
  104 |   operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b) _GLIBCXX_NOTHROW
      |              ~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/ios_base.h:154:3: note: candidate: 'constexpr const std::_Ios_Openmode& std::operator|=(_Ios_Openmode&, _Ios_Openmode)'
  154 |   operator|=(_Ios_Openmode& __a, _Ios_Openmode __b) _GLIBCXX_NOTHROW
      |   ^~~~~~~~
/usr/include/c++/14/bits/ios_base.h:154:29: note:   no known conversion for argument 1 from 'std::vector<bool>::reference' to 'std::_Ios_Openmode&'
  154 |   operator|=(_Ios_Openmode& __a, _Ios_Openmode __b) _GLIBCXX_NOTHROW
      |              ~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/ios_base.h:201:3: note: candidate: 'constexpr const std::_Ios_Iostate& std::operator|=(_Ios_Iostate&, _Ios_Iostate)'
  201 |   operator|=(_Ios_Iostate& __a, _Ios_Iostate __b) _GLIBCXX_NOTHROW
      |   ^~~~~~~~
/usr/include/c++/14/bits/ios_base.h:201:28: note:   no known conversion for argument 1 from 'std::vector<bool>::reference' to 'std::_Ios_Iostate&'
  201 |   operator|=(_Ios_Iostate& __a, _Ios_Iostate __b) _GLIBCXX_NOTHROW
      |              ~~~~~~~~~~~~~~^~~
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:176:
/usr/include/c++/14/future:185:18: note: candidate: 'constexpr std::launch& std::operator|=(launch&, launch)'
  185 |   inline launch& operator|=(launch& __x, launch __y) noexcept
      |                  ^~~~~~~~
/usr/include/c++/14/future:185:37: note:   no known conversion for argument 1 from 'std::vector<bool>::reference' to 'std::launch&'
  185 |   inline launch& operator|=(launch& __x, launch __y) noexcept
      |                             ~~~~~~~~^~~
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:198:
/usr/include/c++/14/charconv:646:3: note: candidate: 'constexpr std::chars_format& std::operator|=(chars_format&, chars_format)'
  646 |   operator|=(chars_format& __lhs, chars_format __rhs) noexcept
      |   ^~~~~~~~
/usr/include/c++/14/charconv:646:28: note:   no known conversion for argument 1 from 'std::vector<bool>::reference' to 'std::chars_format&'
  646 |   operator|=(chars_format& __lhs, chars_format __rhs) noexcept
      |              ~~~~~~~~~~~~~~^~~~~