Language: C++

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

#define ll long long

int main(){

    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    #ifndef ONLINE_JUDGE
    freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
    #endif

    int n,k;
    cin>>n>>k;
    int P[n],C[n],vis[n]={0};
    ll ans=-2*1e18;
    for(int i=0;i<n;i++) cin>>P[i];
    for(int i=0;i<n;i++) cin>>C[i];
    for(int i=0;i<n;i++) ans = max(ans,C[i]);


    for(int i=0;i<n;i++){
        if(vis[i]==1) continue;
        vector<int> v;
        vis[i] = 1;
        v.push_back(C[i]);
        int y=P[i]-1;
        while(y!=i){
            vis[y] = 1;
            v.push_back(C[y]);
            y = P[y]-1;
        }
        // if(i==2) cout<<v[1]<<"\n";
        ll sum1=0,sum2=0;
        int vs = v.size();
        int kp = k%vs;
        for(ll u:v) sum1+=u;
        if(sum1>0) sum1 = sum1*(k/vs);
        else {sum1 = 0; if(k>=vs) kp = vs-1;}
        
        for(int j=0;j<vs;j++){
            sum2=0;
            for(int h=0;h<kp;h++){
                sum2+=v[(j+h)%vs];
                ans = max(ans,sum1+sum2);
                // cout<<sum2<<"\n";
            }
        }
    }




    cout<<ans;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:23:35: error: no matching function for call to 'max(long long int&, int&)'
   23 |     for(int i=0;i<n;i++) ans = max(ans,C[i]);
      |                                ~~~^~~~~~~~~~
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:23:35: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   23 |     for(int i=0;i<n;i++) ans = max(ans,C[i]);
      |                                ~~~^~~~~~~~~~
/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:23:35: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   23 |     for(int i=0;i<n;i++) ans = max(ans,C[i]);
      |                                ~~~^~~~~~~~~~