Language: C++

#include <bits/stdc++.h>

#define PB          push_back
#define PF          push_front
#define MP          make_pair
#define FI          first
#define SE          second
#define SIZE( A )   int( ( A ).size( ) )
#define ALL( A )    ( A ).begin( ), ( A ).end( )
#define ALLR( A )   ( A ).rbegin( ), ( A ).rend( )

using namespace std;

typedef long long           ll;
typedef unsigned long long  ull;
typedef long double         lf;
typedef pair< int, int >    pii;
typedef pair< ll, ll >      pll;
typedef vector< bool >      vb;
typedef vector< lf >        vd;
typedef vector< ll >        vll;
typedef vector< int >       vi;
typedef vector< pii >       vpii;

const int MAXN = int( 2e5 )+10;
const int MOD  = int( 360 );
const int oo   = INT_MAX;
lf PI = acos(-1.0);
lf C = 5.0*PI;

int x1,y1,x2,y2,n, cnt;
pii p[ MAXN ];
int ans;

int _lis( int arr[], int n, int *max_ref)
{
    if (n == 1)
        return 1;
    int res, max_ending_here = 1;
    for (int i = 1; i < n; i++)
    {
        res = _lis(arr, i, max_ref);
        if (arr[i-1] < arr[n-1] && res + 1 > max_ending_here)
            max_ending_here = res + 1;
    }
    if (*max_ref < max_ending_here)
       *max_ref = max_ending_here;

    return max_ending_here;
}

int lis(int arr[], int n)
{
    int max = 1;
    _lis( arr, n, &max );
    return max;
}

int main( ) {

  #ifdef LOCAL
    freopen( "input", "r", stdin );
    //freopen( "output", "w", stdout );
  #else
    //freopen( "input", "r", stdin );
    //freopen( "output", "w", stdout );
    ios_base::sync_with_stdio( 0 );
    cin.tie( 0 );
  #endif
  cout << fixed << setprecision(15);
  cin >> x1 >> y1 >> x2 >> y2 >> n;
  for( int i = 0; i < n; ++i ) {
    int x,y; cin >> x >> y;
    p[i] = make_pair( x,y );
  }
  sort( p, p+n );
  if( x1 > x2 ) {
    swap( x1,x2 );
    swap( y1,y2 );
  }
  ans = (x2-x1) + abs(y2-y1);
  ans *= 100;
  cnt = 0;
  if( x1 == x2 ) {
   auto it = lower_bound( p, p+n, make_pair(x1,-1) );
   if( it != p+n ) {
      ans -= 20;
      cnt += 2;
   }
  }
  else if( y1 == y2 ) {
    auto it = lower_bound( p, p+n, make_pair(x1,y1) );
     if( it != p+n ) {
        ans -= 20;
        cnt += 2;
     }
  }
  else {
    if( y1 < y2 ) {
      int i = 0, cur = 0;
      for( ; i < n; ++i ) {
        if( p[i].FI >= x1 && p[i].SE >= y1 ) break;
      }
      if( i != n ) {
        int sz = n-i;
        int lista[ sz ];
        bool flag = false;
        for( int j = 0; i < n; ++j, ++i ) {
          if( y1 <= p[i].SE && p[i].SE <= y2 ) flag = true;
          lista[ j ] = p[i].SE;
        }
        if(flag)
          cnt = lis( lista, sz );
      }
    }
    else {
      int i = 0, cur = 0;
      for( ; i < n; ++i ) {
        if( p[i].FI >= x1 && p[i].SE <= y1 ) break;
      }
      if( i != n ) {
        int sz = n-i;
        int lista[ sz ];
        bool flag = false;
        for( int j = 0; i < n; ++j, ++i ) {
          if( y2 <= p[i].SE && p[i].SE <= y1 ) flag = true;
          lista[ j ] = -p[i].SE;
        }
        if( flag )
          cnt = lis( lista, sz );
      }
    }
    ans -= 20*cnt;
  }
  cout << ans + cnt*C << '\n';
  return 0;
}


Compiler output:
a.cc:31:8: error: 'int y1' redeclared as different kind of entity
   31 | int x1,y1,x2,y2,n, cnt;
      |        ^~
In file included from /usr/include/features.h:523,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/os_defines.h:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/c++config.h:683,
                 from /usr/include/c++/14/cassert:43,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:33,
                 from a.cc:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:257:1: note: previous declaration 'double y1(double)'
  257 | __MATHCALL (y1,, (_Mdouble_));
      | ^~~~~~~~~~
a.cc: In function 'int main()':
a.cc:71:13: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |   ~~~~~~~~~ ^~ ~~
      |       |        |
      |       |        double(double) noexcept
      |       std::basic_istream<char>::__istream_type {aka std::basic_istream<char>}
In file included from /usr/include/c++/14/sstream:40,
                 from /usr/include/c++/14/complex:45,
                 from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127:
/usr/include/c++/14/istream:170:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(bool&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  170 |       operator>>(bool& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:170:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
/usr/include/c++/14/istream:174:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  174 |       operator>>(short& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:174:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(short int)y1' to 'short int&'
/usr/include/c++/14/istream:177:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(short unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  177 |       operator>>(unsigned short& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:177:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(short unsigned int)y1' to 'short unsigned int&'
/usr/include/c++/14/istream:181:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  181 |       operator>>(int& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:181:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(int)y1' to 'int&'
/usr/include/c++/14/istream:184:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  184 |       operator>>(unsigned int& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:184:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(unsigned int)y1' to 'unsigned int&'
/usr/include/c++/14/istream:188:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  188 |       operator>>(long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:188:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(long int)y1' to 'long int&'
/usr/include/c++/14/istream:192:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  192 |       operator>>(unsigned long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:192:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(long unsigned int)y1' to 'long unsigned int&'
/usr/include/c++/14/istream:199:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  199 |       operator>>(long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:199:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(long long int)y1' to 'long long int&'
/usr/include/c++/14/istream:203:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  203 |       operator>>(unsigned long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:203:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(long long unsigned int)y1' to 'long long unsigned int&'
/usr/include/c++/14/istream:328:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(void*&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  328 |       operator>>(void*& __p)
      |       ^~~~~~~~
/usr/include/c++/14/istream:328:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
a.cc:71:16: error: cannot bind rvalue '(void*)y1' to 'void*&'
/usr/include/c++/14/istream:122:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__istream_type& (*)(__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  122 |       operator>>(__istream_type& (*__pf)(__istream_type&))
      |       ^~~~~~~~
/usr/include/c++/14/istream:122:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'std::basic_istream<char>::__istream_type& (*)(std::basic_istream<char>::__istream_type&)' {aka 'std::basic_istream<char>& (*)(std::basic_istream<char>&)'} [-fpermissive]
   71 |   cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                ^~
      |                |
      |                double (*)(double) noexcept
/usr/include/c++/14/istream:126:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__ios_type& (*)(__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>; __ios_type = std::basic_ios<char>]' (near match)
  126 |       operator>>(__ios_type& (*__pf)(__ios_type&))
      |       ^~~~~~~~
/usr/include/c++/14/istream:126:7: note:   conversion of argument 1 would be ill-formed:
a.cc:71:16: error: invalid conversion from 'double (*)(double) noexcept' to 'std::basic_istream<char>::__ios_type& (*)(std::basic_istream<char>::__ios_type&)' {aka 'std::basic_ios<char>& (