Language: C++

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

vector<ll> w(101,-1),v(101,-1);
map<ll,ll>m;
ll n,w1;
#define mp make_pair

ll solve(ll a,ll b)
{
  	if(a>=n)
      return 0;
  	
 	if(m[mp(a,b)]!=0)
      return m[mp(a,b)];
  	if(b>=w[a]){
		m[mp(a,b)]]=v[a]+solve(a+1,w-v[a]);
    }
  	m[mp(a,b)]]=max(m[mp(a,b)]],solve(a+1,w);
    return m[mp(a,b)]];
}
int main(){
	
  	cin>>n>>w1;
  	
  	for(int i=0;<n;i++){
    	cin>>w[i]>>v[i];
    }
  	cout<<solve(0,w1);
  	return 0;
}

Compiler output:
a.cc: In function 'long long int solve(long long int, long long int)':
a.cc:15:13: error: no match for 'operator[]' (operand types are 'std::map<long long int, long long int>' and 'std::pair<long long int, long long int>')
   15 |         if(m[mp(a,b)]!=0)
      |             ^
In file included from /usr/include/c++/14/map:63,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:152,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'const std::map<long long int, long long int>::key_type&' {aka 'const long long int&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'std::map<long long int, long long int>::key_type&&' {aka 'long long int&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~
a.cc:16:15: error: no match for 'operator[]' (operand types are 'std::map<long long int, long long int>' and 'std::pair<long long int, long long int>')
   16 |       return m[mp(a,b)];
      |               ^
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'const std::map<long long int, long long int>::key_type&' {aka 'const long long int&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'std::map<long long int, long long int>::key_type&&' {aka 'long long int&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~
a.cc:18:18: error: no match for 'operator[]' (operand types are 'std::map<long long int, long long int>' and 'std::pair<long long int, long long int>')
   18 |                 m[mp(a,b)]]=v[a]+solve(a+1,w-v[a]);
      |                  ^
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'const std::map<long long int, long long int>::key_type&' {aka 'const long long int&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'std::map<long long int, long long int>::key_type&&' {aka 'long long int&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~
a.cc:20:10: error: no match for 'operator[]' (operand types are 'std::map<long long int, long long int>' and 'std::pair<long long int, long long int>')
   20 |         m[mp(a,b)]]=max(m[mp(a,b)]],solve(a+1,w);
      |          ^
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'const std::map<long long int, long long int>::key_type&' {aka 'const long long int&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'std::map<long long int, long long int>::key_type&&' {aka 'long long int&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~
a.cc:21:13: error: no match for 'operator[]' (operand types are 'std::map<long long int, long long int>' and 'std::pair<long long int, long long int>')
   21 |     return m[mp(a,b)]];
      |             ^
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'const std::map<long long int, long long int>::key_type&' {aka 'const long long int&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = long long int; _Tp = long long int; _Compare = std::less<long long int>; _Alloc = std::allocator<std::pair<const long long int, long long int> >; mapped_type = long long int; key_type = long long int]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'std::pair<long long int, long long int>' to 'std::map<long long int, long long int>::key_type&&' {aka 'long long int&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~
a.cc:21:22: error: expected ';' before ']' token
   21 |     return m[mp(a,b)]];
      |                      ^
      |                      ;
a.cc:21:22: error: expected primary-expression before ']' token
a.cc: In function 'int main()':
a.cc:27:21: error: expected primary-expression before '<' token
   27 |         for(int i=0;<n;i++){
      |                     ^