Language: C++

#include<bits/stdc++.h>
using namespace std;
template<typename T>
inline void read(T &x)
{
	x=0;
	int f=1;
	char ch=getchar();
	while(ch<'0'||ch>'9')
	{
		if(ch=='-') f=-1;
		ch=getchar();
}
	while(ch>='0'&&ch<='9') x=x*10+(ch^48),ch=getchar();
	x*=f;
	return;
}	
template<typename T>
void write(T x)
{
	if(x<0) putchar('-'),x=-x;
	if(x>=10) write(x/10);
	putchar(x%10+'0');
	return;
}
const int MAXN=5010;
const long long inf=1e18+7;
int n,k;
int p[MAXN];
long long c[MAXN];
int cnt=0;
long long f[MAXN];
long long pre[MAXN];
long long ret=-inf;
int main()
{
    read(n),read(k);
    for(int i=1;i<=n;++i) read(p[i]);
    for(int i=1;i<=n;++i) read(c[i]);
    for(int i=1;i<=n;++i)
    {
        long long ans=0;
        pre[0]=-inf;
        int x=i;
        cnt=0;
        do
        {
            x=p[x];
            ++cnt;
            f[cnt]=f[cnt-1]+c[p[x]];
            pre[cnt]=max(pre[cnt-1],f[cnt]);
        }while(x!=i);
        if(f[cnt]>0)
        {
            ans+=1ll*(k/cnt)*f[cnt];
            if(k%cnt) ans+=max(pre[k%cnt],0);
            ret=max(ret,ans);
        }
        else ret=max(ret,pre[min(k,cnt)]);
    }
    write(ret),putchar('\n');
	return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:56:31: error: no matching function for call to 'max(long long int&, int)'
   56 |             if(k%cnt) ans+=max(pre[k%cnt],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:56:31: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   56 |             if(k%cnt) ans+=max(pre[k%cnt],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:56:31: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   56 |             if(k%cnt) ans+=max(pre[k%cnt],0);
      |                            ~~~^~~~~~~~~~~~~~