Language: C++

#include "bits/stdc++.h"
using namespace std;

// GNU C Compiler
//template<class T> inline string toString(T x) { ostringstream sout; sout << x; return sout.str(); }

// type
using ll = int_fast64_t;
using ull = uint_fast64_t;
using LL = long long;
using ULL = unsigned long long;
using PII = pair<int, int>;
//using pair<T1, T2> = p12;

//container
#define PB emplace_back
#define MP make_pair 
#define SZ(a) int((a).size())
#define ALL(v) v.begin(),v.end()

//repetition
#define REP(n) for(ll i=0; i<(n); i++)
#define REPj(n) for(ll j=0; j<(n); j++)
#define REPinit(i,a,n) for(ll i=(a); i<(n); i++)
#define REPinitj(j,a,n) for(ll j=(a); j<(n); j++)

//algorithm
#define SORT(c) sort((c).begin(),(c).end())
#define CONTAINER_ALL(a) a.begin(),a.end()

//constant

//clear memory
#define CLR(a) memset((a), 0 ,sizeof(a))

//Optimizer
// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")


int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);


    int N, K;
    cin >> N >> K;

    vector<int> P(N), C(N);
    REPinit(i, 0, N) {
        cin >> P[i];
        P[i]--;
    }

    REPinit(i, 0, N) {
        cin >> C[i];
    }

    ll ans = -1 * (ll)1e18;

    REPinit(i, 0, N) {
        int v = i;
        ll cycle_sum = 0;
        int cycle_cnt = 0;

        while (true)
        {
            cycle_cnt++;
            cycle_sum += C[v];
            v = P[v];
            if (v == i) break;
        }

        ll path = 0;
        int cnt = 0;

        while (true)
        {
            cnt++;
            path += C[v];

            if (cnt > K) break;

            int num = (K - cnt) / cycle_cnt;
            ll score = path + max(0ll, cycle_sum) * num;
            if (ans < score) ans = score;

            v = P[v];
            if (v == i) break;
        }
    }

    cout << ans << endl;

    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:86:34: error: no matching function for call to 'max(long long int, ll&)'
   86 |             ll score = path + max(0ll, cycle_sum) * num;
      |                               ~~~^~~~~~~~~~~~~~~~
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:86:34: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'll' {aka 'long int'})
   86 |             ll score = path + max(0ll, cycle_sum) * num;
      |                               ~~~^~~~~~~~~~~~~~~~
/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:86:34: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   86 |             ll score = path + max(0ll, cycle_sum) * num;
      |                               ~~~^~~~~~~~~~~~~~~~