Language: C++

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int main(){
  long long int n,m,k;
  cin >> n >> m >> k;
  vector <long long int> a[n];
  vector <long long int> b[m];
  for(int i=0;i<n;++i){
    long long int input;
    cin >> input;
    a[i].push_back(input);
  }
  for(int i=0;i<m;++i){
    long long int input;
    cin >> input;
    b[i].push_back(input);
  }
  vector <long long int> A[n+1];
  vector <long long int> B[m+1];
  for(int i=0;i<n;++i){
    A[i+1] = A[i] + a[i];
  }
  for(int i=0;i<m;++i){
    B[i+1] = B[i] + b[i];
  }
  int total=0;
  for(int i=0;i<n;++i){
    int other = k-A[i];
    if(other < 0){
      continue;
    }
    long long int l = lower_bound(B.begin(),B.end(),other);
    if(l>m || B[l]>other){
      l--;
    }
    total = max(total,i+l);
  }
  cout << total;
 
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:23:19: error: no match for 'operator+' (operand types are 'std::vector<long long int>' and 'std::vector<long long int>')
   23 |     A[i+1] = A[i] + a[i];
      |              ~~~~ ^ ~~~~
      |                 |      |
      |                 |      vector<[...]>
      |                 vector<[...]>
In file included from /usr/include/c++/14/string:48,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_iterator.h:627:5: note: candidate: 'template<class _Iterator> constexpr std::reverse_iterator<_Iterator> std::operator+(typename reverse_iterator<_Iterator>::difference_type, const reverse_iterator<_Iterator>&)'
  627 |     operator+(typename reverse_iterator<_Iterator>::difference_type __n,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:627:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'const std::reverse_iterator<_Iterator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/stl_iterator.h:1798:5: note: candidate: 'template<class _Iterator> constexpr std::move_iterator<_IteratorL> std::operator+(typename move_iterator<_IteratorL>::difference_type, const move_iterator<_IteratorL>&)'
 1798 |     operator+(typename move_iterator<_Iterator>::difference_type __n,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1798:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'const std::move_iterator<_IteratorL>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
In file included from /usr/include/c++/14/string:54:
/usr/include/c++/14/bits/basic_string.h:3598:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3598 |     operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3598:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3616:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(const _CharT*, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3616 |     operator+(const _CharT* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3616:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   mismatched types 'const _CharT*' and 'std::vector<long long int>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3635:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(_CharT, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3635 |     operator+(_CharT __lhs, const basic_string<_CharT,_Traits,_Alloc>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3635:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3652:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, const _CharT*)'
 3652 |     operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3652:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3670:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, _CharT)'
 3670 |     operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs, _CharT __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3670:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3682:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(__cxx11::basic_string<_CharT, _Traits, _Allocator>&&, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3682 |     operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3682:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3689:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, __cxx11::basic_string<_CharT, _Traits, _Allocator>&&)'
 3689 |     operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3689:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3696:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(__cxx11::basic_string<_CharT, _Traits, _Allocator>&&, __cxx11::basic_string<_CharT, _Traits, _Allocator>&&)'
 3696 |     operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3696:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3719:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(const _CharT*, __cxx11::basic_string<_CharT, _Traits, _Allocator>&&)'
 3719 |     operator+(const _CharT* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3719:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   mismatched types 'const _CharT*' and 'std::vector<long long int>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3726:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(_CharT, __cxx11::basic_string<_CharT, _Traits, _Allocator>&&)'
 3726 |     operator+(_CharT __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3726:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3733:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(__cxx11::basic_string<_CharT, _Traits, _Allocator>&&, const _CharT*)'
 3733 |     operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3733:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
/usr/include/c++/14/bits/basic_string.h:3740:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Allocator> std::operator+(__cxx11::basic_string<_CharT, _Traits, _Allocator>&&, _CharT)'
 3740 |     operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3740:5: note:   template argument deduction/substitution failed:
a.cc:23:24: note:   'std::vector<long long int>' is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   23 |     A[i+1] = A[i] + a[i];
      |                        ^
a.cc:26:19: error: no match for 'operator+' (operand types are 'std::vector<long long int>' and 'std::vector<long long int>')
   26 |     B[i+1] = B[i] + b[i];
      |              ~~~~ ^ ~~~~
      |                 |      |
      |                 |      vector<[...]>
      |                 vector<[...]>
/usr/include/c++/14/bits/stl_iterator.h:627:5: note: candidate: 'temp