Submission #744904

#	Time	Username	Problem	Language	Result	Execution time	Memory
744904		arush_agu	Painting Walls (APIO20_paint)	C++17	Compilation error	0 ms	0 KiB

paint

>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

#ifdef DEBUG
#include <time.h>
#endif

#define all(a) (a).begin(), (a).end()
#define rev(a) (a).rbegin(), (a).rend()
#define F first
#define S second
int recur_depth = 0;
#ifdef DEBUG
#define dbg(x)                                                                 \
  {                                                                            \
    ++recur_depth;                                                             \
    auto x_ = x;                                                               \
    --recur_depth;                                                             \
    cerr << string(recur_depth, '\t') << "\e[91m" << __func__ << ":"           \
         << __LINE__ << "\t" << #x << " = " << x_ << "\e[39m" << endl;         \
  }
#else
#define dbg(x)
#endif

using namespace std;
using namespace __gnu_pbds;

typedef pair<int, int> ii;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> llll;

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vii;
typedef vector<vii> vvii;

typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pair<ll, ll>> vll;
typedef vector<vll> vvll;

typedef vector<bool> vb;

template <class type1>
using ordered_set = tree<type1, null_type, less<type1>, rb_tree_tag,
                         tree_order_statistics_node_update>;

template <typename A, typename B>
ostream &operator<<(ostream &os, const pair<A, B> &p) {
  return os << '(' << p.first << ", " << p.second << ')';
}
template <typename T_container, typename T = typename enable_if<
                                    !is_same<T_container, string>::value,
                                    typename T_container::value_type>::type>
ostream &operator<<(ostream &os, const T_container &v) {
  os << '{';
  string sep;
  for (const T &x : v)
    os << sep << x, sep = ", ";
  return os << '}';
}

const ll MOD = 1e9 + 7;
// const ll MOD = 998244353;
const ll INF = 1e9;
const ld EPS = 1e-9;

int minimumInstructions(int n, int m, int k, vi c, vi a, vvi b) {
  vvi by_col(k); for (int i=0; i<m; i++) for (int col : b[i]) by_col[col].push_back(i);
  for (int i=0; i<n; i++) if (by_col[c[i]].empty()) return -1;

  int mx = 0; for (int i=0; i<k; i++) mx = max(mx, (int)by_col[i].size());

  if (mx == 1) {
    int curr = (by_col[c[0]][0] + 1) % m;
    for (int i = 1; i < n; i++) {
      if (by_col[c[i]].empty() || by_col[c[i]][0] != curr)
        return -1;
      curr = (curr + 1) % m;
    }
    return ((n + m - 1) / m);
  }

  vvi bb(m, vi(k));
  for (int i=0; i<m; i++) {
    for (int col : b[i]) bb[i][col] = 1;
  }

  vb poss(n);
  for (int st=0; st+m<=n; st++) {
    for (int cont : by_col[c[st]]) {
      bool f = 1;
      int cont_id = cont;
      for (int j=st; j<st+m; j++) {
        if (!bb[cont_id][c[j]]) {
          f = 0;
          break;
        }

        cont_id = (cont_id + 1) % m;
      }

      if (f) {
        poss[st] = 1;
        break;
      }
    }
  }

  vb can(n); for (int i=0; i<n; i++) if (poss[i]) {
    for (int j=i; j<i+m; j++) can[j] = 1;
  }
  for (int i=0; i<n; i++) if (!can[i]) {
    return -1;
  }

  int ans = 0;
  int idx = 0;
  while (idx < n) {
    ans++;
    while (!poss[idx]) idx--;
    idx += m;
  }

  return ans;
}

#ifdef DEBUG
void solve() {
  int n, m, k; cin >> n >> m >> k;
  vi c(n); for (int &x : c) cin >> x;
  vi a(m); vvi b(m);
  for (int i=0; i<m; i++) {
    cin >> a[i];
    for (int j=0; j<a[i]; j++) {
      int x; cin >> x;
      b[i].push_back(x);
    }
  }

  cerr << n << " " << m << " " << k << "\n";
  cerr << c << "\n";
  cerr << a << "\n";
  cerr << b << "\n";

  cout << minimumInstructions(n, m, k, c, a, b) << "\n";
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);

  clock_t start = clock();

  int test_cases = 1;
  /* cin >> test_cases; */

  while (test_cases--)
    solve();

  cerr << fixed << setprecision(10)
       << "\nTime Taken: " << (double)(clock() - start) / CLOCKS_PER_SEC
       << "s\n";
  return 0;
}
#endif

Compilation message (stderr)

paint.cpp:1:1: error: expected unqualified-id before '>' token
    1 | >
      | ^
In file included from /usr/include/c++/10/cmath:43,
                 from paint.cpp:3:
/usr/include/c++/10/ext/type_traits.h:162:35: error: 'bool __gnu_cxx::__is_null_pointer' redeclared as different kind of entity
  162 |   __is_null_pointer(std::nullptr_t)
      |                                   ^
/usr/include/c++/10/ext/type_traits.h:157:5: note: previous declaration 'template<class _Type> bool __gnu_cxx::__is_null_pointer(_Type)'
  157 |     __is_null_pointer(_Type)
      |     ^~~~~~~~~~~~~~~~~
/usr/include/c++/10/ext/type_traits.h:162:26: error: 'nullptr_t' is not a member of 'std'
  162 |   __is_null_pointer(std::nullptr_t)
      |                          ^~~~~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:402:26: error: 'std::size_t' has not been declared
  402 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/10/type_traits:403:25: error: '_Size' was not declared in this scope
  403 |     struct is_array<_Tp[_Size]>
      |                         ^~~~~
/usr/include/c++/10/type_traits:403:31: error: template argument 1 is invalid
  403 |     struct is_array<_Tp[_Size]>
      |                               ^
/usr/include/c++/10/type_traits:508:42: error: 'nullptr_t' is not a member of 'std'
  508 |     struct __is_null_pointer_helper<std::nullptr_t>
      |                                          ^~~~~~~~~
/usr/include/c++/10/type_traits:508:51: error: template argument 1 is invalid
  508 |     struct __is_null_pointer_helper<std::nullptr_t>
      |                                                   ^
/usr/include/c++/10/type_traits:1351:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1351 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/10/bits/std_abs.h:38,
                 from /usr/include/c++/10/cmath:47,
                 from paint.cpp:3:
/usr/lib/gcc/x86_64-linux-gnu/10/include/stddef.h:209:23: note: 'size_t' declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:1351:57: error: template argument 1 is invalid
 1351 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                                         ^
/usr/include/c++/10/type_traits:1351:57: note: invalid template non-type parameter
/usr/include/c++/10/type_traits:1360:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1360 |     : public integral_constant<std::size_t, 0> { };
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/10/bits/std_abs.h:38,
                 from /usr/include/c++/10/cmath:47,
                 from paint.cpp:3:
/usr/lib/gcc/x86_64-linux-gnu/10/include/stddef.h:209:23: note: 'size_t' declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:1360:46: error: template argument 1 is invalid
 1360 |     : public integral_constant<std::size_t, 0> { };
      |                                              ^
/usr/include/c++/10/type_traits:1360:46: note: invalid template non-type parameter
/usr/include/c++/10/type_traits:1362:26: error: 'std::size_t' has not been declared
 1362 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/10/type_traits:1363:21: error: '_Size' was not declared in this scope
 1363 |     struct rank<_Tp[_Size]>
      |                     ^~~~~
/usr/include/c++/10/type_traits:1363:27: error: template argument 1 is invalid
 1363 |     struct rank<_Tp[_Size]>
      |                           ^
/usr/include/c++/10/type_traits:1364:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1364 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/10/bits/std_abs.h:38,
                 from /usr/include/c++/10/cmath:47,
                 from paint.cpp:3:
/usr/lib/gcc/x86_64-linux-gnu/10/include/stddef.h:209:23: note: 'size_t' declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:1364:65: error: template argument 1 is invalid
 1364 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                                                 ^
/usr/include/c++/10/type_traits:1364:65: note: invalid template non-type parameter
/usr/include/c++/10/type_traits:1368:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1368 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/10/bits/std_abs.h:38,
                 from /usr/include/c++/10/cmath:47,
                 from paint.cpp:3:
/usr/lib/gcc/x86_64-linux-gnu/10/include/stddef.h:209:23: note: 'size_t' declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:1368:65: error: template argument 1 is invalid
 1368 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                                                 ^
/usr/include/c++/10/type_traits:1368:65: note: invalid template non-type parameter
/usr/include/c++/10/type_traits:1373:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1373 |     : public integral_constant<std::size_t, 0> { };
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/10/bits/std_abs.h:38,
                 from /usr/include/c++/10/cmath:47,
                 from paint.cpp:3:
/usr/lib/gcc/x86_64-linux-gnu/10/include/stddef.h:209:23: note: 'size_t' declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:1373:46: error: template argument 1 is invalid
 1373 |     : public integral_constant<std::size_t, 0> { };
      |                                              ^
/usr/include/c++/10/type_traits:1373:46: note: invalid template non-type parameter
/usr/include/c++/10/type_traits:1375:42: error: 'std::size_t' has not been declared
 1375 |   template<typename _Tp, unsigned _Uint, std::size_t _Size>
      |                                          ^~~
/usr/include/c++/10/type_traits:1376:23: error: '_Size' was not declared in this scope
 1376 |     struct extent<_Tp[_Size], _Uint>
      |                       ^~~~~
/usr/include/c++/10/type_traits:1376:36: error: template argument 1 is invalid
 1376 |     struct extent<_Tp[_Size], _Uint>
      |                                    ^
/usr/include/c++/10/type_traits:1377:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1377 |     : public integral_constant<std::size_t,
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/10/bits/std_abs.h:38,
                 from /usr/include/c++/10/cmath:47,
                 from paint.cpp:3:
/usr/lib/gcc/x86_64-linux-gnu/10/include/stddef.h:209:23: note: 'size_t' declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:1378:24: error: '_Size' was not declared in this scope
 1378 |           _Uint == 0 ? _Size : extent<_Tp,
      |                        ^~~~~
/usr/include/c++/10/type_traits:1379:28: error: template argument 1 is invalid
 1379 |           _Uint - 1>::value>
      |                            ^
/usr/include/c++/10/type_traits:1379:28: note: invalid template non-type parameter
/usr/include/c++/10/type_traits:1384:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1384 |     : public integral_constant<std::size_t,
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/10/bits/std_abs.h:38,
                 from /usr/include/c++/10/cmath:47,
                 from paint.cpp:3:
/usr/lib/gcc/x86_64-linux-gnu/10/include/stddef.h:209:23: note: 'size_t' declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/10/bits/move.h:57,
                 from /usr/include/c++/10/bits/stl_pair.h:59,
                 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 paint.cpp:3:
/usr/include/c++/10/type_traits:1386:31: error: template argument 1 is invalid
 1386 |              _Uint - 1>::value>
      |                               ^
/usr/include/c++/10/type_traits:1386:31: note: invalid template non-type parameter
/usr/include/c++/10/type_traits:1975:26: error: 'std::size_t' has not been declared
 1975 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/10/type_traits:1976:30: error: '_Size' was not declared in this scope
 1976 |     struct remove_extent<_Tp[_Size]>
      |                              ^~~~~
/usr/include/c++/10/type_traits:1976:36: error: template argument 1 is invalid
 1976 |     struct remove_extent<_Tp[_Size]>
      |                                    ^
/usr/include/c++/10/type_traits:1988:26: error: 'std::size_t' has not been declared
 1988 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/10/type_traits:1989:35: error: '_Size' was not declared in this scope
 1989 |     struct remove_all_extents<_Tp[_Size]>
      |                                   ^~~~~
/usr/include/c++/10/type_traits:1989:41: error: template argument 1 is invalid
 1989 |     struct remove_all_extents<_Tp[_Size]>
      |                                         ^
/usr/include/c++/10/type_traits:2047:12: error: 'std::size_t' has not been declared
 2047 |   template<std::size_t _Len>
      |            ^~~
/usr/include/c++/10/type_traits:2052:23: error: '_Len' was not declared in this scope
 2052 |  unsigned char __data[_Len];
      |                       ^~~~
/usr/include/c++/10/type_traits:2067:12: error: 'std::size_t' has not been declared
 2067 |   template<std::size_t _Len, std::size_t _Align =
      |            ^~~
/usr/include/c++/10/type_traits:2067:30: error: 'std::size_t' has not been declared
 2067 |   template<std::size_t _Len, std::size_t _Align =
      |                              ^~~
/usr/include/c++/10/type_traits:2068:48: error: '_Len' was not declared in this scope
 2068 |     __alignof__(typename __aligned_storage_msa<_Len>::__type)>
      |                                                ^~~~
/usr/include/c++/10/type_traits:2068:52: error: template argument 1 is invalid
 2068 |     __alignof__(typename __aligned_storage_msa<_Len>::__type)>
      |                                                    ^
/usr/include/c++/10/type_traits:2073:23: error: '_Len' was not declared in this scope
 2073 |  unsigned char __data[_Len];
      |                       ^~~~
/usr/include/c++/10/type_traits:2074:37: error: '_Align' was not declared in this scope
 2074 |  struct __attribute__((__aligned__((_Align)))) { } __align;
      |                                     ^~~~~~
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 paint.cpp:3:
/usr/include/c++/10/bits/stl_pair.h:92:12: error: 'std::size_t' has not been declared
   92 |   template<std::size_t...>
      |            ^~~
/usr/include/c++/10/bits/stl_pair.h:449:36: error: 'std::size_t' has not been declared
  449 |       template<typename... _Args1, std::size_t... _Indexes1,
      |                                    ^~~
/usr/include/c++/10/bits/stl_pair.h:450:36: error: 'std::size_t' has not been declared
  450 |                typename... _Args2, std::size_t... _Indexes2>
      |                                    ^~~
/usr/include/c++/10/bits/stl_pair.h:453:27: error: '_Indexes1' was not declared in this scope
  453 |              _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>);
      |                           ^~~~~~~~~
/usr/include/c++/10/bits/stl_pair.h:453:36: error: expected parameter pack before '...'
  453 |              _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>);
      |                                    ^~~
/usr/include/c++/10/bits/stl_pair.h:453:39: error: template argument 1 is invalid
  453 |              _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>);
      |                                       ^
/usr/include/c++/10/bits/stl_pair.h:453:55: error: '_Indexes2' was not declared in this scope
  453 |              _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>);
      |                                                       ^~~~~~~~~
/usr/include/c++/10/bits/stl_pair.h:453:64: error: expected parameter pack before '...'
  453 |              _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>);
      |                                                                ^~~
/usr/include/c++/10/bits/stl_pair.h:453:67: error: template argument 1 is invalid
  453 |              _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>);
      |                                                                   ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:65,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from paint.cpp:3:
/usr/include/c++/10/bits/stl_iterator_base_types.h:125:67: error: 'ptrdiff_t' does not name a type
  125 |   template<typename _Category, typename _Tp, typename _Distance = ptrdiff_t,
      |                                                                   ^~~~~~~~~
In file included from /usr/include/c++/10/bits/stl_algobase.h:65,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from paint.cpp:3:
/usr/include/c++/10/bits/stl_iterator_base_types.h:1:1: note: 'ptrdiff_t' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?
  +++ |+#include <cstddef>
    1 | // Types used in iterator implementation -*- C++ -*-
In file included from /usr/include/c++/10/bits/stl_algobase.h:65,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from paint.cpp:3:
/usr/include/c++/10/bits/stl_iterator_base_types.h:214:15: error: 'ptrdiff_t' does not name a type
  214 |       typedef ptrdiff_t                   difference_type;
      |               ^~~~~~~~~
/usr/include/c++/10/bits/stl_iterator_base_types.h:214:15: note: 'ptrdiff_t' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?
/usr/include/c++/10/bits/stl_iterator_base_types.h:225:15: error: 'ptrdiff_t' does not name a type
  225 |       typedef ptrdiff_t                   difference_type;
      |               ^~~~~~~~~
/usr/include/c++/10/bits/stl_iterator_base_types.h:225:15: note: 'ptrdiff_t' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?
In file included from /usr/include/c++/10/bits/stl_algobase.h:66,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from paint.cpp:3:
/usr/include/c++/10/bits/stl_iterator_base_funcs.h:110:5: error: 'ptrdiff_t' does not name a type
  110 |     ptrdiff_t
      |     ^~~~~~~~~
/usr/include/c++/10/bits/stl_iterator_base_funcs.h:66:1: note: 'ptrdiff_t' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?
   65 | #include <debug/assertions.h>
  +++ |+#include <cstddef>
   66 | 
/usr/include/c++/10/bits/stl_iterator_base_funcs.h:116:5: error: 'ptrdiff_t' does not name a type
  116 |     ptrdiff_t
      |     ^~~~~~~~~
/usr/include/c++/10/bits/stl_iterator_base_funcs.h:116:5: note: 'ptrdiff_t' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?
In file included from /usr/include/c++/10/bits/stl_iterator.h:66,
                 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 paint.cpp:3:
/usr/include/c++/10/bits/ptr_traits.h:109:20: error: 'ptrdiff_t' was not declared in this scope
  109 |