Language: C++

#include<bits/stdc++.h>
using namespace std;
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize ("-ffloat-store")  
#pragma GCC optimize ("-fno-defer-pop") 
#define ll long long int
#define ps push_back
#define pb pop_back
#define fs first
#define sc second
#define mkp make_pair
#define mod 1000000007
unordered_map< pair<ll,ll> ,ll> mp;
ll r_knapsack(ll v[],ll wt[],ll W,ll n){
	ll i,j;
	if(mp[{W,n}]>0){
		return mp[{W,n}];
	}
	if(W==0||n==0){//base case
		return 0;
	}
	
	if(wt[n-1]>W){
		return r_knapsack(v,wt,W,n-1);
	}
	else {
		mp[{W,n}]=max(v[n-1]+r_knapsack(v,wt,W-wt[n-1],n-1),r_knapsack(v,wt,W,n-1));
		return mp[{W,n}];	
	}
}
int main(){
	ll i,j,n,W;
	cin>>n>>W;
	ll p[n],w[n];
	for(i=0;i<n;i++){
		cin>>w[i]>>p[i];
	}
	
	ll a=r_knapsack(p,w,W,n);
	cout<<a;
	return 0;
}

Compiler output:
a.cc:14:33: error: use of deleted function 'std::unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map() [with _Key = std::pair<long long int, long long int>; _Tp = long long int; _Hash = std::hash<std::pair<long long int, long long int> >; _Pred = std::equal_to<std::pair<long long int, long long int> >; _Alloc = std::allocator<std::pair<const std::pair<long long int, long long int>, long long int> >]'
   14 | unordered_map< pair<ll,ll> ,ll> mp;
      |                                 ^~
In file included from /usr/include/c++/14/unordered_map:41,
                 from /usr/include/c++/14/functional:63,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:53,
                 from a.cc:1:
/usr/include/c++/14/bits/unordered_map.h:148:7: note: 'std::unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map() [with _Key = std::pair<long long int, long long int>; _Tp = long long int; _Hash = std::hash<std::pair<long long int, long long int> >; _Pred = std::equal_to<std::pair<long long int, long long int> >; _Alloc = std::allocator<std::pair<const std::pair<long long int, long long int>, long long int> >]' is implicitly deleted because the default definition would be ill-formed:
  148 |       unordered_map() = default;
      |       ^~~~~~~~~~~~~
/usr/include/c++/14/bits/unordered_map.h:148:7: error: use of deleted function 'std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits>::_Hashtable() [with _Key = std::pair<long long int, long long int>; _Value = std::pair<const std::pair<long long int, long long int>, long long int>; _Alloc = std::allocator<std::pair<const std::pair<long long int, long long int>, long long int> >; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<long long int, long long int> >; _Hash = std::hash<std::pair<long long int, long long int> >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<true, false, true>]'
In file included from /usr/include/c++/14/bits/unordered_map.h:33:
/usr/include/c++/14/bits/hashtable.h:539:7: note: 'std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits>::_Hashtable() [with _Key = std::pair<long long int, long long int>; _Value = std::pair<const std::pair<long long int, long long int>, long long int>; _Alloc = std::allocator<std::pair<const std::pair<long long int, long long int>, long long int> >; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<long long int, long long int> >; _Hash = std::hash<std::pair<long long int, long long int> >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<true, false, true>]' is implicitly deleted because the default definition would be ill-formed:
  539 |       _Hashtable() = default;
      |       ^~~~~~~~~~
/usr/include/c++/14/bits/hashtable.h:539:7: error: use of deleted function 'std::__detail::_Hashtable_base<_Key, _Value, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _Traits>::_Hashtable_base() [with _Key = std::pair<long long int, long long int>; _Value = std::pair<const std::pair<long long int, long long int>, long long int>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<long long int, long long int> >; _Hash = std::hash<std::pair<long long int, long long int> >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _Traits = std::__detail::_Hashtable_traits<true, false, true>]'
In file included from /usr/include/c++/14/bits/hashtable.h:35:
/usr/include/c++/14/bits/hashtable_policy.h:1731:7: note: 'std::__detail::_Hashtable_base<_Key, _Value, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _Traits>::_Hashtable_base() [with _Key = std::pair<long long int, long long int>; _Value = std::pair<const std::pair<long long int, long long int>, long long int>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<long long int, long long int> >; _Hash = std::hash<std::pair<long long int, long long int> >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _Traits = std::__detail::_Hashtable_traits<true, false, true>]' is implicitly deleted because the default definition would be ill-formed:
 1731 |       _Hashtable_base() = default;
      |       ^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1731:7: error: use of deleted function 'std::__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Hash, _RangeHash, _Unused, __cache_hash_code>::_Hash_code_base() [with _Key = std::pair<long long int, long long int>; _Value = std::pair<const std::pair<long long int, long long int>, long long int>; _ExtractKey = std::__detail::_Select1st; _Hash = std::hash<std::pair<long long int, long long int> >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; bool __cache_hash_code = true]'
/usr/include/c++/14/bits/hashtable_policy.h: In instantiation of 'std::__detail::_Hashtable_ebo_helper<_Nm, _Tp, true>::_Hashtable_ebo_helper() [with int _Nm = 1; _Tp = std::hash<std::pair<long long int, long long int> >]':
/usr/include/c++/14/bits/hashtable_policy.h:1328:7:   required from here
 1328 |       _Hash_code_base() = default;
      |       ^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1245:49: error: use of deleted function 'std::hash<std::pair<long long int, long long int> >::hash()'
 1245 |       _Hashtable_ebo_helper() noexcept(noexcept(_Tp())) : _Tp() { }
      |                                                 ^~~~~
In file included from /usr/include/c++/14/string_view:50,
                 from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52:
/usr/include/c++/14/bits/functional_hash.h:102:12: note: 'std::hash<std::pair<long long int, long long int> >::hash()' is implicitly deleted because the default definition would be ill-formed:
  102 |     struct hash : __hash_enum<_Tp>
      |            ^~~~
/usr/include/c++/14/bits/functional_hash.h:102:12: error: no matching function for call to 'std::__hash_enum<std::pair<long long int, long long int>, false>::__hash_enum()'
/usr/include/c++/14/bits/functional_hash.h:83:7: note: candidate: 'std::__hash_enum<_Tp, <anonymous> >::__hash_enum(std::__hash_enum<_Tp, <anonymous> >&&) [with _Tp = std::pair<long long int, long long int>; bool <anonymous> = false]'
   83 |       __hash_enum(__hash_enum&&);
      |       ^~~~~~~~~~~
/usr/include/c++/14/bits/functional_hash.h:83:7: note:   candidate expects 1 argument, 0 provided
/usr/include/c++/14/bits/functional_hash.h:102:12: error: 'std::__hash_enum<_Tp, <anonymous> >::~__hash_enum() [with _Tp = std::pair<long long int, long long int>; bool <anonymous> = false]' is private within this context
  102 |     struct hash : __hash_enum<_Tp>
      |            ^~~~
/usr/include/c++/14/bits/functional_hash.h:84:7: note: declared private here
   84 |       ~__hash_enum();
      |       ^
/usr/include/c++/14/bits/hashtable_policy.h:1245:49: note: use '-fdiagnostics-all-candidates' to display considered candidates
 1245 |       _Hashtable_ebo_helper() noexcept(noexcept(_Tp())) : _Tp() { }
      |                                                 ^~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1328:7: note: 'std::__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Hash, _RangeHash, _Unused, __cache_hash_code>::_Hash_code_base() [with _Key = std::pair<long long int, long long int>; _Value = std::pair<const std::pair<long long int, long long int>, long long int>; _ExtractKey = std::__detail::_Select1st; _Hash = std::hash<std::pair<long long int, long long int> >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; bool __cache_hash_code = true]' is implicitly deleted because the default definition would be ill-formed:
 1328 |       _Hash_code_base() = default;
      |       ^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1328:7: error: use of deleted function 'std::__detail::_Hashtable_ebo_helper<1, std::hash<std::pair<long long int, long long int> >, true>::~_Hashtable_ebo_helper()'
/usr/include/c++/14/bits/hashtable_policy.h:1242:12: note: 'std::__detail::_Hashtable_ebo_helper<1, std::hash<std::pair<long long int, long long int> >, true>::~_Hashtable_ebo_helper()' is implicitly deleted because the default definition would be ill-formed:
 1242 |     struct _Hashtable_ebo_helper<_Nm, _Tp, true>
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1242:12: error: use of deleted function 'std::hash<std::pair<long long int, long long int> >::~hash()'
/usr/include/c++/14/bits/functional_hash.h:102:12: note: 'std::hash<std::pair<long long int, long long int> >::~hash()' is implicitly deleted because the default definition would be ill-formed:
  102 |     struct hash : __hash_enum<_Tp>
      |            ^~~~
/usr/include/c++/14/bits/functional_hash.h:102:12: error: 'std::__hash_enum<_Tp, <anonymous> >::~__hash_enum() [with _Tp = std::pair<long long int, long long int>; bool <anonymous> = false]' is private within this context
/usr/include/c++/14/bits/functional_hash.h:84:7: note: declared private here
   84 |       ~__hash_enum();
      |       ^
/usr/include/c++/14/bits/hashtable_policy.h:1731:7: note: use '-fdiagnostics-all-candidates' to display considered candidates
 1731 |       _Hashtable_base() = default;
      |       ^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1731:7: error: use of deleted function 'std::__detail::_Hash_code_base<std::pair<long long int, long long int>, std::pair<const std::pair<long long int, long long int>, long long int>, std::__detail::_Select1st, std::hash<std::pair<long long int, long long int> >, std::__detail::_Mod_range_hashing