Language: C++

#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
using namespace std;
using ll = long long;
using P = pair<int,int>;

int main() {
  ll n;
  ll k;
  cin >> n >> k;
  vector<ll> p(n);
  vector<ll> c(n);
  rep(i,n){
    cin >> p[i];
    p[i]-=1;
  }
  rep(i,n){
    cin >> c[i];
  }
  ll res=-10000000000000;
  vector<ll> r(n,0);
  rep(i,n){
    if (r[i]==0){
      vector<ll> a;
      ll b=i;
      while (r[b]==0){
        a.push_back(b);
        r[b]=1;
        b=p[b];
      }
      ll y=0;
      rep(z,a.size()){
        y+=ll(c[a[(z)%a.size()]]);
      }
      if(y>0){
        rep(j,a.size()){
          ll x=0;
          int h=max((k/a.size()-1),ll(0));
          x+= h*y;
          rep(z,k-a.size()*h){
            x+=ll(c[a[(j+z)%a.size()]]);
            if (x>res) res=x;
          }
        }
      }else{
        rep(j,a.size()){
          ll x=0;
          rep(z,a.size()){
            x+=ll(c[a[(j+z)%a.size()]]);
            if (x>res) res=x;
          }
        }
      }



    }
  }
  cout << res << endl;
  return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:38:20: error: no matching function for call to 'max(long long unsigned int, ll)'
   38 |           int h=max((k/a.size()-1),ll(0));
      |                 ~~~^~~~~~~~~~~~~~~~~~~~~~
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:38:20: note:   deduced conflicting types for parameter 'const _Tp' ('long long unsigned int' and 'll' {aka 'long long int'})
   38 |           int h=max((k/a.size()-1),ll(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:
/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:38:20: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long unsigned int'
   38 |           int h=max((k/a.size()-1),ll(0));
      |                 ~~~^~~~~~~~~~~~~~~~~~~~~~