Language: C++

#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll dp[2001][2001][2];
int main(void){
	ll n,i,j,a[2001],temp,x,y,z,t,r,mx;
	cin>>n;
	for(i=0;i<n;i++) cin>>a[i];
	for(i=0;i<=n;i++) for(j=0;j<=n;j++) dp[i][j][0]=-1;
	for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
	for(i=0;i<n-1;i++){
		for(j=0;j<n;j++){
			if(dp[i][j][0]!=-1){
				z=dp[i][j][1];
				x=z-1; y=z+i+1;
				if(x<0) x=n-1;
				if(y>=n) y=y-n;
				if(i%2==1){
					r=a[x]; t=a[y];
					if(dp[i+1][x][0]<dp[i][j][0]+r){
							dp[i+1][x][0]=dp[i][j][0]+r;
							dp[i+1][x][1]=x;
					}
					if(dp[i+1][y][0]<dp[i][j][0]+t){
							dp[i+1][y][0]=dp[i][j][0]+t;
							dp[i+1][y][1]=z;
					}
				}
				else {
					if(a[x]>a[y]){
						if(dp[i+1][x][0]<dp[i][j][0]){
							dp[i+1][x][0]=dp[i][j][0];
							dp[i+1][x][1]=x;
						}
					}
					else {
						if(dp[i+1][y][0]<dp[i][j][0]){
							dp[i+1][y][0]=dp[i][j][0];
							dp[i+1][y][1]=z;
						}
					}
				}
			}
		}
	}
	for(i=0;i<n;i++){
		for(j=0;j<n;j++) cout<<dp[i][j][0]<<' ';
		cout<<endl;
	}
	mx=LLONG_MIN;
	for(i=0;i<n;i++) mx=max(mx,dp[n-1][i][0]);
	cout<<mx<<endl;
	return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:10:19: error: no match for 'operator<' (operand types are 'std::complex<double>' and 'long long int')
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                 ~~^~
      |                 |  |
      |                 |  long long int
      |                 std::complex<double>
In file included from /usr/include/c++/14/regex:68,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:181,
                 from a.cc:1:
/usr/include/c++/14/bits/regex.h:1143:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator<(const sub_match<_BiIter>&, const sub_match<_BiIter>&)'
 1143 |     operator<(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1143:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/regex.h:1224:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator<(__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const sub_match<_BiIter>&)'
 1224 |     operator<(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1224:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/regex.h:1317:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator<(const sub_match<_BiIter>&, __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)'
 1317 |     operator<(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1317:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/regex.h:1391:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)'
 1391 |     operator<(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1391:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'long long int'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/regex.h:1485:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1485 |     operator<(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1485:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/regex.h:1560:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)'
 1560 |     operator<(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1560:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'long long int'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/regex.h:1660:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1660 |     operator<(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1660:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_pair.h:1045:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator<(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1045 |     operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1045:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::pair<_T1, _T2>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:448:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  448 |     operator<(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:448:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::reverse_iterator<_Iterator>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/stl_iterator.h:493:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  493 |     operator<(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:493:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::reverse_iterator<_Iterator>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1694 |     operator<(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::move_iterator<_IteratorL>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1760 |     operator<(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'const std::move_iterator<_IteratorL>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
In file included from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52:
/usr/include/c++/14/string_view:673:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<(basic_string_view<_CharT, _Traits>, basic_string_view<_CharT, _Traits>)'
  673 |     operator< (basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:673:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/string_view:680:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<(basic_string_view<_CharT, _Traits>, __type_identity_t<basic_string_view<_CharT, _Traits> >)'
  680 |     operator< (basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:680:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   'std::complex<double>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/string_view:688:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<(__type_identity_t<basic_string_view<_CharT, _Traits> >, basic_string_view<_CharT, _Traits>)'
  688 |     operator< (__type_identity_t<basic_string_view<_CharT, _Traits>> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:688:5: note:   template argument deduction/substitution failed:
a.cc:10:20: note:   mismatched types 'std::basic_string_view<_CharT, _Traits>' and 'long long int'
   10 |         for(i=0;4i<n;i++) dp[0][i][0]=a[i],dp[0][i][1]=i;
      |                    ^
/usr/include/c++/14/bits/basic_string.h:3874:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3874 |     operator<(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/inc