Language: C++

/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author RiaD
 */

#include <iostream>
#include <fstream>

#include <iostream>
#include <vector>


#include <iterator>


#include <string>
#include <stdexcept>

#ifndef SPCPPL_ASSERT
	#ifdef SPCPPL_DEBUG
		#define SPCPPL_ASSERT(condition) \
		if(!(condition)) { \
			throw std::runtime_error(std::string() + #condition + " in line " + std::to_string(__LINE__) + " in " + __PRETTY_FUNCTION__); \
		}
	#else
		#define SPCPPL_ASSERT(condition)
	#endif
#endif


/**
* Support decrementing and multi-passing, but not declared bidirectional(or even forward) because
* it's reference type is not a reference.
*
* It doesn't return reference because
* 1. Anyway it'll not satisfy requirement [forward.iterators]/6
*   If a and b are both dereferenceable, then a == b if and only if *a and
*   b are bound to the same object.
* 2. It'll not work with reverse_iterator that returns operator * of temporary which is temporary for this iterator
*
* Note, reverse_iterator is not guaranteed to work  now too since it works only with bidirectional iterators,
* but it's seems to work at least on my implementation.
*
* It's not really useful anywhere except iterating anyway.
*/
template <typename T>
class IntegerIterator: public std::iterator<std::input_iterator_tag, T, std::ptrdiff_t, T*, T> {
public:
	explicit IntegerIterator(T value): value(value) {

	}

	IntegerIterator& operator++() {
		++value;
		return *this;
	}

	IntegerIterator operator++(int) {
		IntegerIterator copy = *this;
		++value;
		return copy;
	}

	IntegerIterator& operator--() {
		--value;
		return *this;
	}

	IntegerIterator operator--(int) {
		IntegerIterator copy = *this;
		--value;
		return copy;
	}

	T operator*() const {
		return value;
	}

	bool operator==(IntegerIterator rhs) {
		return value == rhs.value;
	}

	bool operator!=(IntegerIterator rhs) {
		return !(*this == rhs);
	}

private:
	T value;
};

template <typename T>
class IntegerRange {
public:
	IntegerRange(T begin, T end): begin_(begin), end_(end) {
		SPCPPL_ASSERT(begin <= end);
	}

	IntegerIterator<T> begin() const {
		return IntegerIterator<T>(begin_);
	}

	IntegerIterator<T> end() const {
		return IntegerIterator<T>(end_);
	}

private:
	T begin_;
	T end_;
};

template <typename T>
class ReversedIntegerRange {
	typedef std::reverse_iterator<IntegerIterator<T>> IteratorType;
public:
	ReversedIntegerRange(T begin, T end): begin_(begin), end_(end) {
		SPCPPL_ASSERT(begin >= end);
	}

	IteratorType begin() const {
		return IteratorType(IntegerIterator<T>(begin_));
	}

	IteratorType end() const {
		return IteratorType(IntegerIterator<T>(end_));
	}

private:
	T begin_;
	T end_;
};

template <typename T>
IntegerRange<T> range(T to) {
	return IntegerRange<T>(0, to);
}

template <typename T>
IntegerRange<T> range(T from, T to) {
	return IntegerRange<T>(from, to);
}

template <typename T>
IntegerRange<T> inclusiveRange(T to) {
	return IntegerRange<T>(0, to + 1);
}

template <typename T>
IntegerRange<T> inclusiveRange(T from, T to) {
	return IntegerRange<T>(from, to + 1);
}

template <typename T>
ReversedIntegerRange<T> downrange(T from) {
	return ReversedIntegerRange<T>(from, 0);
}

template <typename T>
ReversedIntegerRange<T> downrange(T from, T to) {
	return ReversedIntegerRange<T>(from, to);
}

template <typename T>
ReversedIntegerRange<T> inclusiveDownrange(T from) {
	return ReversedIntegerRange<T>(from + 1, 0);
}

template <typename T>
ReversedIntegerRange<T> inclusiveDownrange(T from, T to) {
	return ReversedIntegerRange<T>(from + 1, to);
}


using namespace std;

class D {
public:
	void solve(std::istream& in, std::ostream& out) {

		int n, k;
		in >> n >> k;
		vector<int> used(n);
		int ans = 0;
		vector<int> v(n);
		for (int i: range(n)) {
			in >> v[i];
			--v[i];
		}
		if (v[0] != 0) {
			++ans;
		}

		v[0] = 0;

		used[0] = true;
		vector<int> dp(n);

		function<int(int)> get = [&](int x) {
			if (used[x])
				return dp[x];
			used[x] = true;
			return dp[x] = get(v[x]) + 1;
		};


		for (int i: range(1, n)) {
			get(i);
			if (dp[i] % k == 1 % k && dp[i] > 1) {
				++ans;
			}
		}
		cerr << endl;

		out << ans;
	}
};


int main() {
	std::ios_base::sync_with_stdio(false);
	D solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	in.tie(0);
	out << std::fixed;
	out.precision(20);
	solver.solve(in, out);
	return 0;
}


Compiler output:
a.cc:48:36: warning: 'template<class _Category, class _Tp, class _Distance, class _Pointer, class _Reference> struct std::iterator' is deprecated [-Wdeprecated-declarations]
   48 | class IntegerIterator: public std::iterator<std::input_iterator_tag, T, std::ptrdiff_t, T*, T> {
      |                                    ^~~~~~~~
In file included from /usr/include/c++/14/bits/stl_iterator_base_funcs.h:66,
                 from /usr/include/c++/14/string:47,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:7:
/usr/include/c++/14/bits/stl_iterator_base_types.h:127:34: note: declared here
  127 |     struct _GLIBCXX17_DEPRECATED iterator
      |                                  ^~~~~~~~
a.cc: In member function 'void D::solve(std::istream&, std::ostream&)':
a.cc:198:17: error: 'function' was not declared in this scope
  198 |                 function<int(int)> get = [&](int x) {
      |                 ^~~~~~~~
a.cc:15:1: note: 'std::function' is defined in header '<functional>'; this is probably fixable by adding '#include <functional>'
   14 | #include <iterator>
  +++ |+#include <functional>
   15 | 
a.cc:198:26: error: expected primary-expression before 'int'
  198 |                 function<int(int)> get = [&](int x) {
      |                          ^~~
a.cc:207:28: error: no matching function for call to 'get(int&)'
  207 |                         get(i);
      |                         ~~~^~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/string:51:
/usr/include/c++/14/bits/stl_pair.h:1250:5: note: candidate: 'template<long unsigned int _Int, class _Tp1, class _Tp2> constexpr typename std::tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type& std::get(pair<_Tp1, _Tp2>&)'
 1250 |     get(pair<_Tp1, _Tp2>& __in) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1250:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::pair<_Tp1, _Tp2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1255:5: note: candidate: 'template<long unsigned int _Int, class _Tp1, class _Tp2> constexpr typename std::tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type&& std::get(pair<_Tp1, _Tp2>&&)'
 1255 |     get(pair<_Tp1, _Tp2>&& __in) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1255:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::pair<_Tp1, _Tp2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1260:5: note: candidate: 'template<long unsigned int _Int, class _Tp1, class _Tp2> constexpr const typename std::tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type& std::get(const pair<_Tp1, _Tp2>&)'
 1260 |     get(const pair<_Tp1, _Tp2>& __in) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1260:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::pair<_Tp1, _Tp2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1265:5: note: candidate: 'template<long unsigned int _Int, class _Tp1, class _Tp2> constexpr const typename std::tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type&& std::get(const pair<_Tp1, _Tp2>&&)'
 1265 |     get(const pair<_Tp1, _Tp2>&& __in) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1265:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::pair<_Tp1, _Tp2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
In file included from /usr/include/c++/14/bits/memory_resource.h:47,
                 from /usr/include/c++/14/string:68:
/usr/include/c++/14/tuple:2445:5: note: candidate: 'template<long unsigned int __i, class ... _Elements> constexpr std::__tuple_element_t<__i, std::tuple<_Elements ...> >& std::get(tuple<_Elements ...>&)'
 2445 |     get(tuple<_Elements...>& __t) noexcept
      |     ^~~
/usr/include/c++/14/tuple:2445:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::tuple<_Elements ...>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/tuple:2451:5: note: candidate: 'template<long unsigned int __i, class ... _Elements> constexpr std::__tuple_element_t<__i, std::tuple<_Elements ...> >& std::get(const tuple<_Elements ...>&)'
 2451 |     get(const tuple<_Elements...>& __t) noexcept
      |     ^~~
/usr/include/c++/14/tuple:2451:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::tuple<_Elements ...>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/tuple:2457:5: note: candidate: 'template<long unsigned int __i, class ... _Elements> constexpr std::__tuple_element_t<__i, std::tuple<_Elements ...> >&& std::get(tuple<_Elements ...>&&)'
 2457 |     get(tuple<_Elements...>&& __t) noexcept
      |     ^~~
/usr/include/c++/14/tuple:2457:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::tuple<_Elements ...>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/tuple:2466:5: note: candidate: 'template<long unsigned int __i, class ... _Elements> constexpr std::__tuple_element_t<__i, std::tuple<_Elements ...> >&& std::get(const tuple<_Elements ...>&&)'
 2466 |     get(const tuple<_Elements...>&& __t) noexcept
      |     ^~~
/usr/include/c++/14/tuple:2466:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::tuple<_Elements ...>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:138:5: note: candidate: 'template<long unsigned int _Int, class _Tp, long unsigned int _Nm> constexpr _Tp& std::get(array<_Tp, _Nm>&)'
  138 |     get(array<_Tp, _Nm>&) noexcept;
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:138:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::array<_Tp, _Nm>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:142:5: note: candidate: 'template<long unsigned int _Int, class _Tp, long unsigned int _Nm> constexpr _Tp&& std::get(array<_Tp, _Nm>&&)'
  142 |     get(array<_Tp, _Nm>&&) noexcept;
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:142:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::array<_Tp, _Nm>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:146:5: note: candidate: 'template<long unsigned int _Int, class _Tp, long unsigned int _Nm> constexpr const _Tp& std::get(const array<_Tp, _Nm>&)'
  146 |     get(const array<_Tp, _Nm>&) noexcept;
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:146:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::array<_Tp, _Nm>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:150:5: note: candidate: 'template<long unsigned int _Int, class _Tp, long unsigned int _Nm> constexpr const _Tp&& std::get(const array<_Tp, _Nm>&&)'
  150 |     get(const array<_Tp, _Nm>&&) noexcept;
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:150:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::array<_Tp, _Nm>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1272:5: note: candidate: 'template<class _Tp, class _Up> constexpr _Tp& std::get(pair<_T1, _T2>&)'
 1272 |     get(pair<_Tp, _Up>& __p) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1272:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::pair<_T1, _T2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1277:5: note: candidate: 'template<class _Tp, class _Up> constexpr const _Tp& std::get(const pair<_T1, _T2>&)'
 1277 |     get(const pair<_Tp, _Up>& __p) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1277:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::pair<_T1, _T2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1282:5: note: candidate: 'template<class _Tp, class _Up> constexpr _Tp&& std::get(pair<_T1, _T2>&&)'
 1282 |     get(pair<_Tp, _Up>&& __p) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1282:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'std::pair<_T1, _T2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1287:5: note: candidate: 'template<class _Tp, class _Up> constexpr const _Tp&& std::get(const pair<_T1, _T2>&&)'
 1287 |     get(const pair<_Tp, _Up>&& __p) noexcept
      |     ^~~
/usr/include/c++/14/bits/stl_pair.h:1287:5: note:   template argument deduction/substitution failed:
a.cc:207:28: note:   mismatched types 'const std::pair<_T1, _T2>' and 'int'
  207 |                         get(i);
      |                         ~~~^~~
/usr/include/c++/14/bits/stl_pair.h:1292:5: note: candidate: 'template<class _Tp, class _Up> constexpr _Tp& std::get(pair<_Up, _Tp>&)'
 1292 |     get(pair<_Up, _Tp