Language: C++

#include <iostream>
#include <vector>
#include <algorithm>
#include <iomanip>
#include <string>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <tuple>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cassert>
#include <cstdint>
#include <cctype>
#include <numeric>
#include <bitset>
#include <functional>

using namespace std;

using ll =  long long;
using Pll = pair<ll, ll>;
using Pii = pair<int, int>;

constexpr int INF = 1 << 30;
constexpr ll LINF = 1LL << 60;
constexpr ll MOD = 1000000007;
constexpr long double EPS = 1e-10;
constexpr int dyx[4][2] = {
    { 0, 1}, {-1, 0}, {0,-1}, {1, 0}
};

int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);
    int n; ll m, v, p;
    cin >> n >> m >> v >> p;
    vector<ll> a(n);
    for(int i=0;i<n;++i) cin >> a[i];
    sort(a.rbegin(), a.rend());

    int ok = p-1, ng = n;
    while(ng-ok > 1) {
        int mid = (ok+ng) / 2;

        if(a[mid] + m < a[p-1]) {
            ng = mid;
            continue;
        }

        ll votes = m * (v - (n-mid) - (p-1));
        for(int i=p-1;i<mid;++i) {
            votes -= max(a[mid]+m - a[i], 0);
        }

        if(votes <= 0) {
            ok = mid;
        } else {
            ng = mid;
        }
    }

    cout << ok+1 << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:55:25: error: no matching function for call to 'max(__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type, int)'
   55 |             votes -= max(a[mid]+m - a[i], 0);
      |                      ~~~^~~~~~~~~~~~~~~~~~~~
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:55:25: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   55 |             votes -= max(a[mid]+m - a[i], 0);
      |                      ~~~^~~~~~~~~~~~~~~~~~~~
/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:55:25: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   55 |             votes -= max(a[mid]+m - a[i], 0);
      |                      ~~~^~~~~~~~~~~~~~~~~~~~