답안 #888600

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
888600	2023-12-18T01:12:26 Z	ad_red	Tri (CEOI09_tri)	C++17	컴파일 오류	0 ms	0 KB

tri

#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> B;
typedef long long ll;
typedef pair<int,int> PII;
// head
  
const int N=100100;
const int S=1200;
int n,m;
  
struct pt {
  int x,y;
  pt(int _x=0,int _y=0) : x(_x),y(_y) {}
}p[N];

ll vp(pt a, pt b) {
  return a.x * b.y - b.x * a.y;
}

vector<pt> ch[N];
int orient(pt a,pt b,pt c) {
  ll v=(b.y-a.y)*1ll*(c.x-b.x)-(b.x-a.x)*1ll*(c.y-b.y);
  return v==0?0:(v<0?-1:1);
}

ll sgn(pt a, pt b, pt c) {
  // -1 if the order is A-B-C from left to right if B is the bottom point
  // 1 or 0 otherwise
  
  ll q = (a.x - b.x) * (c.y - b.y) - (a.y - b.y) * (c.x - b.x);
  return q == 0 ? 0 : (q < 0 ? -1 : 1);
}

bool const operator<(const pt& a,const pt& b) {
  if (orient(pt(0,0),a,b)==0) {
    return (a.x==b.x?a.y<b.y:a.x<b.x);
  }
  return orient(pt(0,0),a,b)>0;
}

bool in_tri(pt a,pt b,pt c,pt p) {
  return orient(a,b,p)!=-1&&orient(b,c,p)!=-1&&orient(c,a,p)!=-1;
}

int main() {
  scanf("%d%d",&n,&m);
  rep(i,0,n) {
    scanf("%d%d",&p[i].x,&p[i].y);
  }
  sort(p,p+n);
  rep(i,0,n) {
    ch[i/S].pb(p[i]);
  }
  rep(i,0,n) {
    if (ch[i].empty()) continue;
    vector<pt> hull;
    sort(all(ch[i]),[&](pt a,pt b) { return a.x<b.x||(a.x==b.x&&a.y<b.y); });
    for (auto& p:ch[i]) {
      while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
        hull.pop_back();
      }
      hull.pb(p);
    }
    ch[i]=hull;
  }
  while (m--) {
    pt a,b;
    scanf("%d%d%d%d",&a.x,&a.y,&b.x,&b.y);
    if (orient(b,pt(0,0),a)<=0) swap(a,b);
    int L,R;
    {
      L=n-1;
      int low=0,high=n-1;
      while (low<=high) {
        int mid=low+high>>1;
        if (orient(p[mid],pt(0,0),a)>=0) {
          L=mid;
          high=mid-1;
        } else {
          low=mid+1;
        }
      }
    }
    {
      R=0;
      int low=0,high=n-1;
      while (low<=high) {
        int mid=low+high>>1;
        if (orient(p[mid],pt(0,0),b)<=0) {
          R=mid;
          low=mid+1;
        } else {
          high=mid-1;
        }
      }
    }
    if (L>R) {
      printf("N\n");
      continue;
    }
    if (R-L<=S) {
      bool ok=false;
      rep(i,L,R+1) if (in_tri(a,b,pt(0,0),p[i])) ok=true;
      puts(ok?"Y":"N");
      continue;
    }
    bool ok=false;
    while (L%S!=0) {
      if (in_tri(a,b,pt(0,0),p[L])) ok=true;
      L++;
    }
    while (R>=L&&R%S!=S-1) {
      if (in_tri(a,b,pt(0,0),p[R])) ok=true;
      R--;
    }
    rep(i,L/S,R/S+1) {
      int sz=SZ(ch[i]);
      int low=0,high=sz-1;
      while (low<=high) {
        int mid=low+high>>1;
        if (in_tri(a,b,pt(0,0),ch[i][mid])) {
          ok=true;
          break;
        }
        if (mid+1==sz||(!in_tri(a,b,pt(0,0),ch[i][mid+1])&&orient(ch[i][mid],a,ch[i][mid+1])==1)) {
          high=mid-1;
        } else {
          low=mid+1;
        }
      }
      if (ok) break;
    }
    puts(ok?"Y":"N");
  }
}

Compilation message

tri.cpp: In function 'int main()':
tri.cpp:70:48: warning: right operand of comma operator has no effect [-Wunused-value]
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                ^
tri.cpp:70:69: error: no match for 'operator<=' (operand types are '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} and 'int')
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^~ ~
      |                                                 |                      |
      |                                                 |                      int
      |                                                 __gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type {aka pt}
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from tri.cpp:1:
/usr/include/c++/10/bits/regex.h:1086:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator<=(const std::__cxx11::sub_match<_BiIter>&, const std::__cxx11::sub_match<_BiIter>&)'
 1086 |     operator<=(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1086:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from tri.cpp:1:
/usr/include/c++/10/bits/regex.h:1192:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator<=(std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const std::__cxx11::sub_match<_BiIter>&)'
 1192 |     operator<=(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1192:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from tri.cpp:1:
/usr/include/c++/10/bits/regex.h:1285:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator<=(const std::__cxx11::sub_match<_BiIter>&, std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)'
 1285 |     operator<=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1285:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from tri.cpp:1:
/usr/include/c++/10/bits/regex.h:1359:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<=(const typename std::iterator_traits<_Iter>::value_type*, const std::__cxx11::sub_match<_BiIter>&)'
 1359 |     operator<=(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1359:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from tri.cpp:1:
/usr/include/c++/10/bits/regex.h:1453:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<=(const std::__cxx11::sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1453 |     operator<=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1453:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from tri.cpp:1:
/usr/include/c++/10/bits/regex.h:1531:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<=(const typename std::iterator_traits<_Iter>::value_type&, const std::__cxx11::sub_match<_BiIter>&)'
 1531 |     operator<=(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1531:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from tri.cpp:1:
/usr/include/c++/10/bits/regex.h:1631:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<=(const std::__cxx11::sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1631 |     operator<=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1631:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:64,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from tri.cpp:1:
/usr/include/c++/10/bits/stl_pair.h:508:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator<=(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)'
  508 |     operator<=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_pair.h:508:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::pair<_T1, _T2>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from tri.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:384:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<=(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)'
  384 |     operator<=(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:384:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::reverse_iterator<_Iterator>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from tri.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:422:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<=(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)'
  422 |     operator<=(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:422:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::reverse_iterator<_Iterator>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from tri.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:1460:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<=(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorR>&)'
 1460 |     operator<=(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:1460:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::move_iterator<_IteratorL>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from tri.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:1513:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<=(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorL>&)'
 1513 |     operator<=(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:1513:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::move_iterator<_IteratorL>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/basic_string.h:48,
                 from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from tri.cpp:1:
/usr/include/c++/10/string_view:582:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<=(std::basic_string_view<_CharT, _Traits>, std::basic_string_view<_CharT, _Traits>)'
  582 |     operator<=(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/10/string_view:582:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   'pt' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/basic_string.h:48,
                 from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from tri.cpp:1:
/usr/include/c++/10/string_view:588:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<=(std::basic_string_view<_CharT, _Traits>, std::__type_identity_t<std::basic_string_view<_CharT, _Traits> >)'
  588 |     operator<=(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/10/string_view:588:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   'pt' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/bits/basic_string.h:48,
                 from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from tri.cpp:1:
/usr/include/c++/10/string_view:595:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<=(std::__type_identity_t<std::basic_string_view<_CharT, _Traits> >, std::basic_string_view<_CharT, _Traits>)'
  595 |     operator<=(__type_identity_t<basic_string_view<_CharT, _Traits>> __x,
      |     ^~~~~~~~
/usr/include/c++/10/string_view:595:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   mismatched types 'std::basic_string_view<_CharT, _Traits>' and 'int'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from tri.cpp:1:
/usr/include/c++/10/bits/basic_string.h:6343:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<=(const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>&, const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 6343 |     operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/basic_string.h:6343:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from tri.cpp:1:
/usr/include/c++/10/bits/basic_string.h:6356:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<=(const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>&, const _CharT*)'
 6356 |     operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/basic_string.h:6356:5: note:   template argument deduction/substitution failed:
tri.cpp:70:72: note:   '__gnu_cxx::__alloc_traits<std::allocator<pt>, pt>::value_type' {aka 'pt'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   70 |       while (SZ(hull)>=2 && (hull[SZ(hull)-2], p, hull[SZ(hull)-1]) <= 0) {
      |                                                                        ^
In file included from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/local