Language: C++

#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
#include<math.h>
#include<string.h>
using namespace std;
typedef long long ll;
typedef pair<int, int>P;

ll n, k;
ll t[100010], d[100010];
ll ans = 0;

void dfs(int i, int count, ll sat, vector<int> kind) {
	if (count == k) {
		ans = max(ans, sat + (ll)kind.size()*kind.size());
		return;
	}
	if (i == n) {
		return;
	}
	bool flag = true;
	for (int j = 0; j < kind.size(); j++) {
		if (kind[j] == t[i]) {
			flag = false;
		}
	}
	dfs(i + 1, count, sat, kind);
	if (flag) {
		kind.push_back(t[i]);
	}
	dfs(i + 1, count + 1, sat + d[i], kind);
}

int main() {
	cin >> n >> k;
	for (int i = 0; i < n; i++) {
		cin >> t[i] >> d[i];
	}
	dfs(0, 0, 0, {});
	cout << ans << endl;
	return 0;
}

Compiler output:
a.cc: In function 'void dfs(int, int, ll, std::vector<int>)':
a.cc:17:26: error: no matching function for call to 'max(ll&, long long unsigned int)'
   17 |                 ans = max(ans, sat + (ll)kind.size()*kind.size());
      |                       ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/string:51,
                 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:1:
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:17:26: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'long long unsigned int')
   17 |                 ans = max(ans, sat + (ll)kind.size()*kind.size());
      |                       ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
In file included from /usr/include/c++/14/algorithm:61,
                 from a.cc:3:
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:17:26: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   17 |                 ans = max(ans, sat + (ll)kind.size()*kind.size());
      |                       ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~