Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vll;
typedef pair<ll, ll> P;

int main() {
    ll n, k;
    cin >> n >> k;
    vector<P> sushis(n);
    for (int i = 0; i < n; ++i) {
        cin >> sushis[i].second >> sushis[i].first;
    }
    sort(sushis.begin(), sushis.end(), greater<P>());
    ll ans = 0;
    set<ll> st;
    stack<P> sk;
    for (int i = 0; i < k; ++i) {
        if (st.count(sushis[i].second)) {
            sk.push(sushis[i]);
        }
        st.insert(sushis[i].second);
        ans += sushis[i].first;
    }
    ll curr = ans;
    ans += st.size() * st.size();
    for (int i = k; i < n; ++i) {
        if (sk.empty()) break;
        if (st.count(sushis[i].second)) continue;
        curr -= sk.top().first;
        sk.pop();
        curr += sushis[i].first;
        st.insert(sushis[i].second);
        ans = max(ans, (ll) curr + st.size() * st.size());
    }
    cout << ans << endl;
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:34:18: error: no matching function for call to 'max(ll&, long long unsigned int)'
   34 |         ans = max(ans, (ll) curr + st.size() * st.size());
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 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:34:18: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'long long unsigned int')
   34 |         ans = max(ans, (ll) curr + st.size() * st.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:
/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:34:18: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   34 |         ans = max(ans, (ll) curr + st.size() * st.size());
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~