Language: C++

#include <iostream>
#include <array>
#include <vector>
#include <iomanip>
#include <string>
#include <cmath>
#include <algorithm>
#include <queue>
#include <map>
#include <set>

using namespace std;

typedef  pair<int,int> P;
typedef long long LL;
typedef vector<LL> VEC;
typedef vector<LL> VVEC;


const LL INF=1<<30;
const LL MOD=1000000007;

LL gcd(LL a,LL b){
    if(b==0)return a;

    return gcd(b,a%b);
}

LL kaijo(LL n){
    LL ans=1;
    for(LL i=1;i<=n;++i){
        (ans*=i)%=MOD;
    }
    return ans;
}


int main(){
    int h,w;
    cin>>h>>w;
    int n;
    cin>>n;
    VEC a(n);
    VVEC ans(h,VEC(w));
    for(int i=1;i<=n;++i){
        cin>>a[i];
    }
    
    //sort(a.begin(),a.end(),greater<LL>());
    int k=1;
    for(int i=0;i<h;i++){
        if(i%2==0){
            for(int j=0;j<w;++j){
                ans[i][j]=k;
                a[k]--;
                if(a[k]==0)k++;
            }

        }else{
                for(int j=w-1;j>=0;--j){
                ans[i][j]=k;
                a[k]--;
                if(a[k]==0)k++;
            }

        }
    }
    for(int i=0;i<h;++i){
        for(int j=0;j<w;++j){
            cout<<ans[i][j]<<" ";
        }
        cout<<"\n";
    }
    cout<<endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:44:22: error: no matching function for call to 'std::vector<long long int>::vector(int&, VEC)'
   44 |     VVEC ans(h,VEC(w));
      |                      ^
In file included from /usr/include/c++/14/vector:66,
                 from a.cc:3:
/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 = long long int; _Alloc = std::allocator<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:44:22: note:   deduced conflicting types for parameter '_InputIterator' ('int' and 'std::vector<long long int>')
   44 |     VVEC ans(h,VEC(w));
      |                      ^
/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 = long long int; _Alloc = std::allocator<long long int>; allocator_type = std::allocator<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 'int' to 'std::initializer_list<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 = long long int; _Alloc = std::allocator<long long int>; std::__type_identity_t<_Alloc> = std::allocator<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 'int' to '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 = long long int; _Alloc = std::allocator<long long int>; allocator_type = std::allocator<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 = long long int; _Alloc = std::allocator<long long int>; allocator_type = std::allocator<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 = long long int; _Alloc = std::allocator<long long int>; std::__type_identity_t<_Alloc> = std::allocator<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 'int' to 'const 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 = long long int; _Alloc = std::allocator<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 = long long int; _Alloc = std::allocator<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 = long long int; _Alloc = std::allocator<long long int>; size_type = long unsigned int; value_type = long long int; allocator_type = std::allocator<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 'VEC' {aka 'std::vector<long long int>'} to 'const std::vector<long long int>::value_type&' {aka 'const 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 = long long int; _Alloc = std::allocator<long long int>; size_type = long unsigned int; allocator_type = std::allocator<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 'VEC' {aka 'std::vector<long long int>'} to 'const std::vector<long long int>::allocator_type&' {aka 'const std::allocator<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 = long long int; _Alloc = std::allocator<long long int>; allocator_type = std::allocator<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 = long long int; _Alloc = std::allocator<long long int>]'
  531 |       vector() = default;
      |       ^~~~~~
/usr/include/c++/14/bits/stl_vector.h:531:7: note:   candidate expects 0 arguments, 2 provided
a.cc:54:23: error: invalid types '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type {aka long long int}[int]' for array subscript
   54 |                 ans[i][j]=k;
      |                       ^
a.cc:61:23: error: invalid types '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type {aka long long int}[int]' for array subscript
   61 |                 ans[i][j]=k;
      |                       ^
a.cc:70:25: error: invalid types '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type {aka long long int}[int]' for array subscript
   70 |             cout<<ans[i][j]<<" ";
      |                         ^