Language: C++

#include <stdio.h>
#include <assert.h>
#include <fstream>
#include <iostream>
#include <algorithm>
#include <array>
#include <vector>
#include <queue>
#include <set>
#include <cmath>
#include <iomanip>
//#include <unordered_map>
//#include <unordered_set>
//#include <boost/container/static_vector.hpp>
//#include <boost/unordered_set.hpp>
//#include <boost/unordered_map.hpp>
//#include <unistd.h>

//#include <cv.h>
//#include <highgui.h>
#include <stdlib.h>
#include <string>

const int MAX_N = 200050;
const int MAX_L = 100000000;
int x1, y1, x2, y2;
int N;
int X[MAX_N], Y[MAX_N];

int seq[MAX_N], dp_lis[MAX_N];

int main(int argc, char **argv) {
    std::cin >> x1 >> y1 >> x2 >> y2;
    std::cin >> N;

    for (int i = 1; i <= N; i++) {
        std::cin >> X[i] >> Y[i];
    }

    if (x2 < x1) {
        for (int i = 1; i <= N; i++) {
            X[i] = MAX_L - 1 - X[i];
        }
        x1 = MAX_L - 1 - x1;
        x2 = MAX_L - 1 - x2;
    }

    if (y2 < y1) {
        for (int i = 1; i <= N; i++) {
            Y[i] = MAX_L - 1 - Y[i];
        }
        y1 = MAX_L - 1 - y1;
        y2 = MAX_L - 1 - y2;
    }

    std::vector<std::pair<int, int>> vec;

    for (int i = 1; i <= N; i++) {
        if (x1 <= X[i] && X[i] <= x2 && y1 <= Y[i] && Y[i] <= y2) {
            vec.push_back(std::pair<int, int>({X[i], Y[i]}));
        }
    }

    std::sort(vec.begin(), vec.end(),
        [](const std::pair<int, int>& a, const std::pair<int, int> b) { return a.first < b.first; }
    );

    int seq_size = vec.size();

    for (int i = 1; i <= seq_size; i++) {
        seq[i] = vec[i-1].second;
    }

    for (int i = 1; i <= seq_size; i++) {
        dp_lis[i] = MAX_L;
    }
    dp_lis[0] = 0;

    for (int i = 1; i <= seq_size; i++) {
        int lb = 0;
        int ub = seq_size;
        while(lb + 1 < ub) {
            int mid = (lb + ub) / 2;
            if (dp_lis[mid] < seq[i]) {
                lb = mid;
            } else {
                ub = mid;
            }
        }
        dp_lis[ub] = std::min(dp_lis[ub], seq[i]);
    }

    int length = 0;
    for (int i = 1; i <= seq_size; i++) {
        if (dp_lis[i] < MAX_L) {
            length++;
        } else {
            break;
        }
    }

    double PI = acos(-1.0);

    double ret = (x2 - x1 + y2 - y1) * 100.0;

    if (length == std::min(x2 - x1 + 1, y2 - y1 + 1)) {
        ret += (length - 1) * (5.0 * PI - 20.0);
        ret += 10.0 * PI - 20.0;
    } else {
        ret += length * (5.0 * PI - 20.0);
    }

    std::cout << std::setprecision(14) << ret << std::endl;

    return 0;
}

Compiler output:
a.cc:26:9: error: 'int y1' redeclared as different kind of entity
   26 | int x1, y1, x2, y2;
      |         ^~
In file included from /usr/include/features.h:523,
                 from /usr/include/x86_64-linux-gnu/bits/libc-header-start.h:33,
                 from /usr/include/stdio.h:28,
                 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(int, char**)':
a.cc:33:20: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |     ~~~~~~~~~~~~~~ ^~ ~~
      |              |        |
      |              |        double(double) noexcept
      |              std::basic_istream<char>::__istream_type {aka std::basic_istream<char>}
In file included from /usr/include/c++/14/fstream:40,
                 from a.cc:3:
/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:33:23: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
/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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       double (*)(double) noexcept
a.cc:33:23: 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:33:23: 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]
   33 |     std::cin >> x1 >> y1 >> x2 >> y2;
      |                       ^~
      |                       |
      |                       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:33:23: 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>& (*)(std::basic_ios<char>&)'} [-fpermissive]