Language: C++

#include <bits/stdc++.h>
#define mod 1000000007
#define pb push_back
#define ll long long
using namespace std;
int main(){
	int n,k;
	cin>>n>>k;
	vector<ll> a(n+2),psum(n+2),ksum(n+2);
	for(int i=1;i<=n;i++){
		cin>>a[i];
		psum[i] = psum[i-1] + max(a[i],0);
	}
	for(int i=1;i<=k;i++){
		ksum[1]+=a[i];
	}
	for(int i=k+1;i<=n;i++){
		ksum[i-k+1] = ksum[i-k] + a[i] - a[i-k];
	}
	ll ans=-1;
	for(int i=1;i<=n-k+1;i++){
		ll tmp=0;
		tmp += max(ksum[i],0);
		tmp += psum[i-1];
		tmp += psum[n] - psum[i+k-1];
		if(ans<tmp)ans=tmp;
	}
	cout<<ans<<endl;
	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:12:42: error: no matching function for call to 'max(__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type&, int)'
   12 |                 psum[i] = psum[i-1] + max(a[i],0);
      |                                       ~~~^~~~~~~~
In file included from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:12:42: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   12 |                 psum[i] = psum[i-1] + max(a[i],0);
      |                                       ~~~^~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
In file included from /usr/include/c++/14/algorithm:61:
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:12:42: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   12 |                 psum[i] = psum[i-1] + max(a[i],0);
      |                                       ~~~^~~~~~~~
a.cc:23:27: error: no matching function for call to 'max(__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type&, int)'
   23 |                 tmp += max(ksum[i],0);
      |                        ~~~^~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:23:27: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   23 |                 tmp += max(ksum[i],0);
      |                        ~~~^~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:23:27: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   23 |                 tmp += max(ksum[i],0);
      |                        ~~~^~~~~~~~~~~