Language: C++

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

typedef long long ll;
typedef vector< int > vi;
typedef vector< vi > vvi;
typedef pair< int,int > ii;
// #define f(i,a,b) for(int (int)i = (int)a;i<b;i++)
// #define rf((i),(a),(b)) for(int (i) = b; (i)>(a);(i--))
#define sz(a) int((a).size())
#define pb push_back
#define all(c) (c).begin(),(c).end()
#define tr(c,i) for(typeof((c)).begin() i = (c).begin(); i != (c).end(); i++)
#define present(c,x) ((c).find(x) != (c).end())
#define cpresent(c,x) (find(all(c),x) != (c).end())
#define mp make_pair

int main(void)
{
    ios_base::sync_with_stdio(false);
    ll n,w;
    cin >> n >> w;
    vector<pair<ll,ll>> val;
    for(int i = 0;i<n;i++)
    {
        int temp1,temp2;
        cin >> temp1 >> temp2;
        val.pb(mp(temp1,temp2));
    }
    vector<vector<ll>> dp(n+1,vi(w+1,0));//note where the variable name comes here.
    for(int i = 1;i<=n;i++)
        for(int j=1;j<=w;j++)
            if(val[i-1].first<=j)
                dp[i][j] = max((val[i-1].second + dp[i-1][j-val[i-1].first]),dp[i-1][j]);
            else
                dp[i][j] = dp[i-1][j];
    
    cout << dp[n][w];
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:30:40: error: no matching function for call to 'std::vector<std::vector<long long int> >::vector(ll, vi)'
   30 |     vector<vector<ll>> dp(n+1,vi(w+1,0));//note where the variable name comes here.
      |                                        ^
In file included from /usr/include/c++/14/vector:66,
                 from /usr/include/c++/14/functional:64,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:53,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_vector.h:707:9: note: candidate: 'template<class _InputIterator, class> std::vector<_Tp, _Alloc>::vector(_InputIterator, _InputIterator, const allocator_type&) [with <template-parameter-2-2> = _InputIterator; _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >]'
  707 |         vector(_InputIterator __first, _InputIterator __last,
      |         ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:707:9: note:   template argument deduction/substitution failed:
a.cc:30:40: note:   deduced conflicting types for parameter '_InputIterator' ('long long int' and 'std::vector<int>')
   30 |     vector<vector<ll>> dp(n+1,vi(w+1,0));//note where the variable name comes here.
      |                                        ^
/usr/include/c++/14/bits/stl_vector.h:678:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::initializer_list<_Tp>, const allocator_type&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; allocator_type = std::allocator<std::vector<long long int> >]'
  678 |       vector(initializer_list<value_type> __l,
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:678:43: note:   no known conversion for argument 1 from 'll' {aka 'long long int'} to 'std::initializer_list<std::vector<long long int> >'
  678 |       vector(initializer_list<value_type> __l,
      |              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_vector.h:659:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&, std::__type_identity_t<_Alloc>&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; std::__type_identity_t<_Alloc> = std::allocator<std::vector<long long int> >]'
  659 |       vector(vector&& __rv, const __type_identity_t<allocator_type>& __m)
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:659:23: note:   no known conversion for argument 1 from 'll' {aka 'long long int'} to 'std::vector<std::vector<long long int> >&&'
  659 |       vector(vector&& __rv, const __type_identity_t<allocator_type>& __m)
      |              ~~~~~~~~~^~~~
/usr/include/c++/14/bits/stl_vector.h:640:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&, const allocator_type&, std::false_type) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; allocator_type = std::allocator<std::vector<long long int> >; std::false_type = std::false_type]'
  640 |       vector(vector&& __rv, const allocator_type& __m, false_type)
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:640:7: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_vector.h:635:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&, const allocator_type&, std::true_type) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; allocator_type = std::allocator<std::vector<long long int> >; std::true_type = std::true_type]'
  635 |       vector(vector&& __rv, const allocator_type& __m, true_type) noexcept
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:635:7: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_vector.h:624:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(const std::vector<_Tp, _Alloc>&, std::__type_identity_t<_Alloc>&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; std::__type_identity_t<_Alloc> = std::allocator<std::vector<long long int> >]'
  624 |       vector(const vector& __x, const __type_identity_t<allocator_type>& __a)
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:624:28: note:   no known conversion for argument 1 from 'll' {aka 'long long int'} to 'const std::vector<std::vector<long long int> >&'
  624 |       vector(const vector& __x, const __type_identity_t<allocator_type>& __a)
      |              ~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_vector.h:620:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >]'
  620 |       vector(vector&&) noexcept = default;
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:620:7: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_vector.h:601:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(const std::vector<_Tp, _Alloc>&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >]'
  601 |       vector(const vector& __x)
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:601:7: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_vector.h:569:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(size_type, const value_type&, const allocator_type&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; size_type = long unsigned int; value_type = std::vector<long long int>; allocator_type = std::allocator<std::vector<long long int> >]'
  569 |       vector(size_type __n, const value_type& __value,
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:569:47: note:   no known conversion for argument 2 from 'vi' {aka 'std::vector<int>'} to 'const std::vector<std::vector<long long int> >::value_type&' {aka 'const std::vector<long long int>&'}
  569 |       vector(size_type __n, const value_type& __value,
      |                             ~~~~~~~~~~~~~~~~~~^~~~~~~
/usr/include/c++/14/bits/stl_vector.h:556:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(size_type, const allocator_type&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; size_type = long unsigned int; allocator_type = std::allocator<std::vector<long long int> >]'
  556 |       vector(size_type __n, const allocator_type& __a = allocator_type())
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:556:51: note:   no known conversion for argument 2 from 'vi' {aka 'std::vector<int>'} to 'const std::vector<std::vector<long long int> >::allocator_type&' {aka 'const std::allocator<std::vector<long long int> >&'}
  556 |       vector(size_type __n, const allocator_type& __a = allocator_type())
      |                             ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_vector.h:542:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(const allocator_type&) [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >; allocator_type = std::allocator<std::vector<long long int> >]'
  542 |       vector(const allocator_type& __a) _GLIBCXX_NOEXCEPT
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:542:7: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_vector.h:531:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector() [with _Tp = std::vector<long long int>; _Alloc = std::allocator<std::vector<long long int> >]'
  531 |       vector() = default;
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:531:7: note:   candidate expects 0 arguments, 2 provided