Language: C++

#include <bits/stdc++.h>
using namespace std;
const long double PI=3.14159265358979323846;

int main() {
	long double x1,y1,x2,y2;
	scanf("%Lf%Lf%Lf%Lf", &x1, &y1, &x2, &y2);
	if (x1>x2) {
		swap(x1,x2);
		swap(y1,y2);
	}
	int n;
	scanf("%d", &n);
	vector<pair<long double, long double> > v;
	bool FLAG=false;
	for (int i=0; i<n; i++) {
		long double x, y;
		scanf("%Lf%Lf", &x, &y);
		if (x1<=x && x<=x2) {
			if (y1==y2) FLAG=true;
			if (y1<=y2 && y1<=y && y<=y2) {
				FLAG|=x1==x2;
				v.push_back({x,y});
			}
			if (y2<=y1 && y2<=y && y<=y1) {
				FLAG|=x1==x2;
				v.push_back({x,y});
			}
		}
	}
	sort(v.begin(), v.end());
	vector<long double> vl;
	if (y1<=y2) {
		for (int i=0; i<v.size(); i++) {
			if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
		else if (vl.empty()||v[i].second>vl.back()) vl.push_back(v[i].second);
		else {
			int loc=lower_bound(vl.begin(),vl.end(),v[i].second)-vl.begin();
			vl[loc]=v[i].second;
		}
	}
}
else {
	for (int i=0; i<v.size(); i++) {
			if (!v.empty() && v[i].second=-v.back()+1 && v[i].second==y2) FLAG=true;
		else if (vl.empty()||-v[i].second>vl.back()) vl.push_back(-v[i].second);
		else {
			int loc=lower_bound(vl.begin(),vl.end(),-v[i].second)-vl.begin();
			vl[loc]=-v[i].second;
		}
	}
}
	//printf("%d\n", vl.size());
	long double ans=(long double)(abs(x2-x1)+abs(y2-y1))*(long double)100;
	if (!FLAG) ans+=(long double)(PI*5.0-20.0)*(long double)vl.size();
	if (FLAG) ans+=(PI*10.0-20.0);
	printf("%.12Lf\n", ans);
}


Compiler output:
a.cc: In function 'int main()':
a.cc:35:63: error: no match for 'operator+' (operand types are '__gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type' {aka 'std::pair<long double, long double>'} and 'int')
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                       ~~~~~~~~^~
      |                                                             |  |
      |                                                             |  int
      |                                                             __gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type {aka std::pair<long double, long double>}
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:35:64: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'int'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'int'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
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:35:64: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type' {aka 'std::pair<long double, long double>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   mismatched types 'const _CharT*' and 'std::pair<long double, long double>'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>' and 'int'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type' {aka 'std::pair<long double, long double>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type' {aka 'std::pair<long double, long double>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type' {aka 'std::pair<long double, long double>'} is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type' {aka 'std::pair<long double, long double>'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64: note:   '__gnu_cxx::__alloc_traits<std::allocator<std::pair<long double, long double> >, std::pair<long double, long double> >::value_type' {aka 'std::pair<long double, long double>'} is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   35 |                         if (!v.empty() && v[i].second=v.back()+1 && v[i].second==y2) FLAG=true;
      |                                                                ^
/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:35:64