Language: C++

include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file  
#include <ext/pb_ds/tree_policy.hpp>  
#include <functional> // for less  
using namespace         std;
#define                 int long long
#define                 pb push_back
#define                 mp make_pair
#define st(arr,a)       memset(arr,a,sizeof arr)
#define                 nl cout<<endl
#define                 endl '\n'              
#define bitcount(x)     __builtin_popcountll(x)
const int MOD = 1000000007ll;
#define forn(i,a,b)     for(int i=a;i<=b;i++)
#define rfor(i,a,b)     for(int i=a;i>=b;i--)
#define all(x)          x.begin() , x.end()
#define pi pair<int,int>
#define X first
#define Y second
#define N 1014159
#define  vi vector<int>
#define  v  vector
using namespace __gnu_pbds;  
typedef tree<int, null_type, less<int>, rb_tree_tag,  
            tree_order_statistics_node_update> oset; 
gp_hash_table<int, int> table;
const int RANDOM = chrono::high_resolution_clock::now().time_since_epoch().count();
struct chash {
    int operator()(int x) const { return x ^ RANDOM; }
};
 
vi adj[N];
int visited[N];
int cmp;
int arr[N];
 
void dfs(int u)
{
    visited[u] = 1;
    for(auto i : adj[u])
    {
        if(visited[i] == 0){
            dfs(i);
        }
    }
}
 
void solve()
{
    int n,m;
    cin>>n>>m;
    forn(i,1,n)cin>>arr[i];
    forn(i,1,m)
    {
        int a,b;
        cin>>a>>b;
        adj[a].pb(b);
        adj[b].pb(a);
    }
    
    forn(i,1,n)
    {
        if(visited[i] == 0)
        {
            dfs(i);
            cmp++;
        }
    }
    
    if(n<2*(cmp-1))
    {
        cout<<"Impossible";
    }
}
 
 
signed main() 
{
    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); 
    int t = 1;
    //cin>>t;
    while(t--)
    {
        solve();
    }
 
 
 
    return 0;
 
}
 
//       g++ -g c.cpp ; ./a.exe


Compiler output:
a.cc:1:1: error: 'include' does not name a type
    1 | include<bits/stdc++.h>
      | ^~~~~~~
In file included from /usr/include/c++/14/ext/typelist.h:46,
                 from /usr/include/c++/14/ext/pb_ds/assoc_container.hpp:45,
                 from a.cc:2:
/usr/include/c++/14/ext/type_traits.h:164:35: error: 'constexpr const bool __gnu_cxx::__is_null_pointer' redeclared as different kind of entity
  164 |   __is_null_pointer(std::nullptr_t)
      |                                   ^
/usr/include/c++/14/ext/type_traits.h:159:5: note: previous declaration 'template<class _Type> constexpr bool __gnu_cxx::__is_null_pointer(_Type)'
  159 |     __is_null_pointer(_Type)
      |     ^~~~~~~~~~~~~~~~~
/usr/include/c++/14/ext/type_traits.h:164:26: error: 'nullptr_t' is not a member of 'std'
  164 |   __is_null_pointer(std::nullptr_t)
      |                          ^~~~~~~~~
In file included from /usr/include/c++/14/bits/stl_pair.h:60,
                 from /usr/include/c++/14/utility:69,
                 from /usr/include/c++/14/ext/pb_ds/detail/type_utils.hpp:46,
                 from /usr/include/c++/14/ext/pb_ds/tag_and_trait.hpp:46,
                 from /usr/include/c++/14/ext/pb_ds/assoc_container.hpp:46:
/usr/include/c++/14/type_traits:666:33: error: 'nullptr_t' is not a member of 'std'; did you mean 'nullptr_t'?
  666 |     struct is_null_pointer<std::nullptr_t>
      |                                 ^~~~~~~~~
In file included from /usr/include/c++/14/cstddef:50,
                 from /usr/include/c++/14/ext/pb_ds/detail/type_utils.hpp:45:
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:443:29: note: 'nullptr_t' declared here
  443 |   typedef decltype(nullptr) nullptr_t;
      |                             ^~~~~~~~~
/usr/include/c++/14/type_traits:666:42: error: template argument 1 is invalid
  666 |     struct is_null_pointer<std::nullptr_t>
      |                                          ^
/usr/include/c++/14/type_traits:670:48: error: template argument 1 is invalid
  670 |     struct is_null_pointer<const std::nullptr_t>
      |                                                ^
/usr/include/c++/14/type_traits:674:51: error: template argument 1 is invalid
  674 |     struct is_null_pointer<volatile std::nullptr_t>
      |                                                   ^
/usr/include/c++/14/type_traits:678:57: error: template argument 1 is invalid
  678 |     struct is_null_pointer<const volatile std::nullptr_t>
      |                                                         ^
/usr/include/c++/14/type_traits:1429:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1429 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1429:57: error: template argument 1 is invalid
 1429 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                                         ^
/usr/include/c++/14/type_traits:1429:57: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:1438:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1438 |     : public integral_constant<std::size_t, 0> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1438:46: error: template argument 1 is invalid
 1438 |     : public integral_constant<std::size_t, 0> { };
      |                                              ^
/usr/include/c++/14/type_traits:1438:46: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:1440:26: error: 'std::size_t' has not been declared
 1440 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/type_traits:1441:21: error: '_Size' was not declared in this scope
 1441 |     struct rank<_Tp[_Size]>
      |                     ^~~~~
/usr/include/c++/14/type_traits:1441:27: error: template argument 1 is invalid
 1441 |     struct rank<_Tp[_Size]>
      |                           ^
/usr/include/c++/14/type_traits:1442:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1442 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1442:65: error: template argument 1 is invalid
 1442 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                                                 ^
/usr/include/c++/14/type_traits:1442:65: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:1446:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
 1446 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/type_traits:1446:65: error: template argument 1 is invalid
 1446 |     : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
      |                                                                 ^
/usr/include/c++/14/type_traits:1446:65: note: invalid template non-type parameter
/usr/include/c++/14/type_traits:2086:26: error: 'std::size_t' has not been declared
 2086 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/type_traits:2087:30: error: '_Size' was not declared in this scope
 2087 |     struct remove_extent<_Tp[_Size]>
      |                              ^~~~~
/usr/include/c++/14/type_traits:2087:36: error: template argument 1 is invalid
 2087 |     struct remove_extent<_Tp[_Size]>
      |                                    ^
/usr/include/c++/14/type_traits:2099:26: error: 'std::size_t' has not been declared
 2099 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/type_traits:2100:35: error: '_Size' was not declared in this scope
 2100 |     struct remove_all_extents<_Tp[_Size]>
      |                                   ^~~~~
/usr/include/c++/14/type_traits:2100:41: error: template argument 1 is invalid
 2100 |     struct remove_all_extents<_Tp[_Size]>
      |                                         ^
/usr/include/c++/14/type_traits:2171:12: error: 'std::size_t' has not been declared
 2171 |   template<std::size_t _Len>
      |            ^~~
/usr/include/c++/14/type_traits:2176:30: error: '_Len' was not declared in this scope
 2176 |         unsigned char __data[_Len];
      |                              ^~~~
/usr/include/c++/14/type_traits:2194:12: error: 'std::size_t' has not been declared
 2194 |   template<std::size_t _Len, std::size_t _Align =
      |            ^~~
/usr/include/c++/14/type_traits:2194:30: error: 'std::size_t' has not been declared
 2194 |   template<std::size_t _Len, std::size_t _Align =
      |                              ^~~
/usr/include/c++/14/type_traits:2195:55: error: '_Len' was not declared in this scope
 2195 |            __alignof__(typename __aligned_storage_msa<_Len>::__type)>
      |                                                       ^~~~
/usr/include/c++/14/type_traits:2195:59: error: template argument 1 is invalid
 2195 |            __alignof__(typename __aligned_storage_msa<_Len>::__type)>
      |                                                           ^
/usr/include/c++/14/type_traits:2202:30: error: '_Len' was not declared in this scope
 2202 |         unsigned char __data[_Len];
      |                              ^~~~
/usr/include/c++/14/type_traits:2203:44: error: '_Align' was not declared in this scope
 2203 |         struct __attribute__((__aligned__((_Align)))) { } __align;
      |                                            ^~~~~~
In file included from /usr/include/c++/14/ext/pb_ds/detail/type_utils.hpp:47:
/usr/include/c++/14/tr1/type_traits:153:26: error: 'std::size_t' has not been declared
  153 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/14/tr1/type_traits:154:25: error: '_Size' was not declared in this scope
  154 |     struct is_array<_Tp[_Size]>
      |                         ^~~~~
/usr/include/c++/14/tr1/type_traits:154:31: error: template argument 1 is invalid
  154 |     struct is_array<_Tp[_Size]>
      |                               ^
/usr/include/c++/14/tr1/type_traits:354:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  354 |     : public integral_constant<std::size_t, __alignof__(_Tp)> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/tr1/type_traits:354:61: error: template argument 1 is invalid
  354 |     : public integral_constant<std::size_t, __alignof__(_Tp)> { };
      |                                                             ^
/usr/include/c++/14/tr1/type_traits:354:61: note: invalid template non-type parameter
/usr/include/c++/14/tr1/type_traits:359:37: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  359 |     : public integral_constant<std::size_t, 0> { };
      |                                     ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/tr1/type_traits:359:46: error: template argument 1 is invalid
  359 |     : public integral_constant<std::size_t, 0> { };
      |                                              ^
/usr/include/c++/14/tr1