Language: C++

#include <iostream>
#include <vector>
#include <utility>
#include <map>
#include <algorithm>
using namespace std;

typedef long long ll;
ll N, W;
map<pair<ll, ll> , ll> dp; //<i番目まで見たときの重さに対する価値の最大値>
vector<ll> w, v;

ll func(ll, ll);
int main(){
  cin >> N >> W;
  ll wt, vt;
  w.push_back(0); v.push_back(0);
  for(int i=1; i<=N; i++) {
    cin >> wt >> vt;
    w.push_back(wt);
    v.push_back(vt);
  }

  for(int i=0; i<=W; i++){
    dp[make_pair(0, i)] = 0;
  }
  for(int i=0; i<=N; i++){
    dp[make_pair(i, 0)] = 0;
  }

  ll ans=0;
  for(int i=max(w[0]-3, 0); i<=W; i++){
    ans = max(ans, func(N, i));
  }

  cout << ans << endl;

  return 0;
}

ll func(ll i, ll wm){
  pair<ll, ll> tmp = make_pair(i, wm);
  if(dp.find(tmp)==dp.end()){
    if(wm<w[i]){
      return dp[tmp]=func(i-1, wm);
    }
    else{
      return dp[tmp]=max(func(i-1, wm), func(i-1, wm-w[i])+v[i]);
    }
  }
  else{
    return dp[tmp];
  }
}


Compiler output:
a.cc: In function 'int main()':
a.cc:32:16: error: no matching function for call to 'max(__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type, int)'
   32 |   for(int i=max(w[0]-3, 0); i<=W; i++){
      |             ~~~^~~~~~~~~~~
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:32:16: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   32 |   for(int i=max(w[0]-3, 0); i<=W; 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,
                 from a.cc:5:
/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:32:16: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   32 |   for(int i=max(w[0]-3, 0); i<=W; i++){
      |             ~~~^~~~~~~~~~~