Language: C++

#include <bits/stdc++.h>
using namespace std;

int main()
{
	cin.tie(0);
	ios::sync_with_stdio(false);

	int h,w;
	cin >>h>>w;
	vector<vector<char> > s(h, vector<char>(w));
	for(int i =0;i<h;i++)
			scanf("%s", s[i]+1);
			
	int total = 1;
	for(int i =0;i<h;i++)
		for(int j=0;j<w;j++)
		{
			//center sij;
			int cnt=0;
			if(s[i][j]=='.')
				cnt = -3;
			else
			{
				continue;
			}
			int m,n;
			for(m=i,n=j;n>=0;n--)
				{if(s[m][n]=='.')
					{
						cnt++;
					}
					else
						break;}
			for(m=i,n=j;n<w;n++)
				{if(s[m][n]=='.')
					{
						cnt++;
					}
					else
						break;}
			for(m=i,n=j;m>=0;m--)
				{if(s[m][n]=='.')
					{
						cnt++;
					}
					else
						break;}
			for(m=i,n=j;m<h;m++)
				{if(s[m][n]=='.')
					{
						cnt++;
					}
					else
						break;}
			if(total<cnt)
				total=cnt;
		}
		cout <<total<<endl;
	return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:13:41: error: no match for 'operator+' (operand types are '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} and 'int')
   13 |                         scanf("%s", s[i]+1);
In file included from /usr/include/c++/14/bits/stl_algobase.h:67,
                 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_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:13:42: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'int'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'int'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
In file included 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/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:13:42: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   mismatched types 'const _CharT*' and 'std::vector<char>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>' and 'int'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   mismatched types 'const _CharT*' and 'std::vector<char>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   mismatched types 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>' and 'int'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/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:13:42: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::vector<char> >, std::vector<char> >::value_type' {aka 'std::vector<char>'} is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   13 |                         scanf("%s", s[i]+1);
      |                                          ^
/usr/include/c++/14/bits/basic_string.h:3740:5: note: candidate: '