Language: C++

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ff(i,a,b) for(i=a;i<=b;i++)
#define fb(i,a,b) for(i=a;i>=b;i--)
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL)
#define 1000000007
int main()
{
    fast;
    ll n,i,total=0;
    bool ans=false;
    cin>>n;
    ll a[n+1];
    unordered_map<ll,ll> m;
    ff(i,1,n)
    {
        cin>>a[i];
        if(n & 1)
        {
            if(a[i] & 1)
                ans=true;
        }
        else
        {
            if(a[i]%2==0)
                ans=true;
        }
        if(a[i]>=n)
            ans=true;
        m[a[i]]++;
    }
    for(auto x : m)
    {
        if(n & 1)
        {
            if(m[0]!=1)
            {
                ans=true;
                break;
            }
            else if(x.second!=2 && x.first!=0)
            {
                ans=true;
                break;
            }
        }
        else
        {
            if(x.second!=2)
            {
                ans=true;
                break;
            }
        }

    }
    if(ans)
    {
        cout<<"0"<<endl;
    }
    else
    {
        if(n & 1)
        {
            total=(long long)(pow(2,n/2)%m);
            cout<<total%m<<endl;
        }
        else
        {
            total=(long long)(pow(2,n/2)%m);
            cout<<total%m<<endl;
        }
    }
    return 0;
}


Compiler output:
a.cc:7:9: error: macro names must be identifiers
    7 | #define 1000000007
      |         ^~~~~~~~~~
a.cc: In function 'int main()':
a.cc:66:41: error: no match for 'operator%' (operand types are '__gnu_cxx::__promote<double>::__type' {aka 'double'} and 'std::unordered_map<long long int, long long int>')
   66 |             total=(long long)(pow(2,n/2)%m);
      |                               ~~~~~~~~~~^~
      |                                  |       |
      |                                  |       std::unordered_map<long long int, long long int>
      |                                  __gnu_cxx::__promote<double>::__type {aka double}
In file included from /usr/include/c++/14/valarray:605,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:166,
                 from a.cc:1:
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom1, class _Dom2> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_Expr, _Dom1, _Dom2>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const _Expr<_Dom2, typename _Dom2::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and '__gnu_cxx::__promote<double>::__type' {aka 'double'}
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_Constant, _Dom, typename _Dom::value_type>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const typename _Dom::value_type&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and '__gnu_cxx::__promote<double>::__type' {aka 'double'}
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Constant, std::_Expr, typename _Dom::value_type, _Dom>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const typename _Dom::value_type&, const _Expr<_Dom1, typename _Dom1::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   'std::unordered_map<long long int, long long int>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_ValArray, _Dom, typename _Dom::value_type>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const valarray<typename _Dom::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and '__gnu_cxx::__promote<double>::__type' {aka 'double'}
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_ValArray, std::_Expr, typename _Dom::value_type, _Dom>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const valarray<typename _Dom::value_type>&, const _Expr<_Dom1, typename _Dom1::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   'std::unordered_map<long long int, long long int>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
/usr/include/c++/14/valarray:1200:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_ValArray, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__modulus, _Tp>::result_type> std::operator%(const valarray<_Tp>&, const valarray<_Tp>&)'
 1200 | _DEFINE_BINARY_OPERATOR(%, __modulus)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1200:1: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   mismatched types 'const std::valarray<_Tp>' and '__gnu_cxx::__promote<double>::__type' {aka 'double'}
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
/usr/include/c++/14/valarray:1200:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_ValArray, std::_Constant, _Tp, _Tp>, typename std::__fun<std::__modulus, _Tp>::result_type> std::operator%(const valarray<_Tp>&, const typename valarray<_Tp>::value_type&)'
 1200 | _DEFINE_BINARY_OPERATOR(%, __modulus)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1200:1: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   mismatched types 'const std::valarray<_Tp>' and '__gnu_cxx::__promote<double>::__type' {aka 'double'}
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
/usr/include/c++/14/valarray:1200:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Constant, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__modulus, _Tp>::result_type> std::operator%(const typename valarray<_Tp>::value_type&, const valarray<_Tp>&)'
 1200 | _DEFINE_BINARY_OPERATOR(%, __modulus)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1200:1: note:   template argument deduction/substitution failed:
a.cc:66:42: note:   'std::unordered_map<long long int, long long int>' is not derived from 'const std::valarray<_Tp>'
   66 |             total=(long long)(pow(2,n/2)%m);
      |                                          ^
a.cc:67:24: error: no match for 'operator%' (operand types are 'long long int' and 'std::unordered_map<long long int, long long int>')
   67 |             cout<<total%m<<endl;
      |                   ~~~~~^~
      |                   |     |
      |                   |     std::unordered_map<long long int, long long int>
      |                   long long int
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom1, class _Dom2> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_Expr, _Dom1, _Dom2>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const _Expr<_Dom2, typename _Dom2::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:67:25: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and 'long long int'
   67 |             cout<<total%m<<endl;
      |                         ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_Constant, _Dom, typename _Dom::value_type>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const typename _Dom::value_type&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:67:25: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and 'long long int'
   67 |             cout<<total%m<<endl;
      |                         ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Constant, std::_Expr, typename _Dom::value_type, _Dom>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const typename _Dom::value_type&, const _Expr<_Dom1, typename _Dom1::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:67:25: note:   'std::unordered_map<long long int, long long int>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
   67 |             cout<<total%m<<endl;
      |                         ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_ValArray, _Dom, typename _Dom::value_type>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const valarray<t