Language: C++

#include <bits/stdc++.h> 
using namespace std; 
#define in(x) int x; cin>>x;
#define sin(s) string s; cin>>s;
#define ll long long int 
#define lin(x) ll x; cin>>x;
#define vi vector<int>
#define vll vector<ll>
#define si set<int>
#define pb push_back
#define re(i,n) for(ll i=0; i<n; i++)
#define pe(i,a,b) for(ll i=a; i<=b; i++)
#define rre(i,n) for(int i=n-1; i>-1; i--) 
#define mp make_pair
#define pii pair<ll,ll>
#define endl "\n"
#define pi 3.1415926536 
#define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define fio freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout);
#define mod 1000000007
#define inf INT_MAX
/////////////////////////////////////////////////////////////////////////////////

bool compare(const pair<int, int>&i, const pair<int, int>&j) 
{ 
        if(i.second==j.second)
                return i.first>j.first;
        return i.second> j.second; 
} 
/////////////////////////////////////////////////////////////////////////////////
//vi v;
int ncr(int n, int k)   
{   
        if(n<k)
                return 0;
        int C[n + 1][k + 1];   
        int i, j;   
        for (i = 0; i <= n; i++)   
        {   
                for (j = 0; j <= min(i, k); j++)   
                {   
                        if (j == 0 || j == i)   
                                C[i][j] = 1;   
                        else  
                                C[i][j] = (C[i - 1][j - 1] + C[i - 1][j])%mod;   
                }   
        }   
        return C[n][k];   
} 
////////////////////////////////////////////////////////////////////////////
ll modpowIter(ll a, ll b, ll c)   
{   
        int ans=1;  
        while(b != 0)   
        {  
                if(b%2 == 1) 
                ans=(ans*a)%c;  
                a=(a*a)%c;  
                b /= 2;   
        }  
        return ans;  
} 
///////////////////////////////////////////////////////////////////////////////
string intobin(int n)
{
        string s="";
        if(n==0)
                s="0";
        while(n)
        {
                if(n%2)
                        s="1"+s;
                else
                        s="0"+s;
                n/=2;
        }
        return s;
}

////////////////////////////////////////////////////////////////////////////////

int bintoin(string s)
{
        ll n=0;
        vll v;
        v.pb(1);
        re(i,400)
        {
                v.pb((v[v.size()-1]*2)%1000003);
        }
        rre(i,s.length())
        {
                n=(n+(s[i]-'0')*v[s.length()-i-1])%1000003;
                //cout<<v[s.length()-i-1]<<endl;
        }
        return n;
}
//////////////////////////////////////////////////////////////////////////////////
ll nc2(ll n, ll k)
{
        if(n<k)
                return 0;
        return (n*(n-1))/2;
}
///////////////////////////////////////////////////////////////////////////////////
bool prime[1000001]; 
void SieveOfEratosthenes(int n)   
{     
        memset(prime, true, sizeof(prime));   
        for (int p=2; p*p<=n; p++)   
        {    
                if (prime[p] == true)   
                {   
                        for (int i=p*p; i<=n; i += p)   
                        prime[i] = false;   
                }   
        }   
        /*for (int p=2; p<=n; p++)   
                if (prime[p])   
                        v.pb(p);  */
}   
////////////////////////////////////////////////////////////////////////////////////
int main()
{
        FAST
        in(n)
        in(n>=30)
                cout<<"Yes";
        else
                cout<<"No";
        return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:127:13: error: expected initializer before '>=' token
  127 |         in(n>=30)
      |             ^~
a.cc:3:19: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                   ^
a.cc:127:13: error: no match for 'operator>=' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'int')
  127 |         in(n>=30)
      |             ^~~~
      |               |
      |               int
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
a.cc:127:13: note: candidate: 'operator>=(int, int)' (built-in)
  127 |         in(n>=30)
      |             ^
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
a.cc:127:13: note:   no known conversion for argument 1 from 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} to 'int'
  127 |         in(n>=30)
      |             ^
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
In file included from /usr/include/c++/14/regex:68,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:181,
                 from a.cc:1:
/usr/include/c++/14/bits/regex.h:1165:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator>=(const sub_match<_BiIter>&, const sub_match<_BiIter>&)'
 1165 |     operator>=(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1165:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/regex.h:1248:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator>=(__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const sub_match<_BiIter>&)'
 1248 |     operator>=(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1248:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/regex.h:1341:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator>=(const sub_match<_BiIter>&, __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)'
 1341 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1341:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/regex.h:1415:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)'
 1415 |     operator>=(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1415:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/regex.h:1509:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1509 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1509:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/regex.h:1586:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)'
 1586 |     operator>=(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1586:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/regex.h:1686:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1686 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1686:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_pair.h:1070:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator>=(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1070 |     operator>=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1070:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::pair<_T1, _T2>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:476:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator>=(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  476 |     operator>=(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:476:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::reverse_iterator<_Iterator>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/stl_iterator.h:520:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>=(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  520 |     operator>=(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:520:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::reverse_iterator<_Iterator>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/stl_iterator.h:1724:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>=(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1724 |     operator>=(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1724:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::move_iterator<_IteratorL>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
/usr/include/c++/14/bits/stl_iterator.h:1781:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator>=(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1781 |     operator>=(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1781:5: note:   template argument deduction/substitution failed:
a.cc:127:15: note:   'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} is not derived from 'const std::move_iterator<_IteratorL>'
  127 |         in(n>=30)
      |               ^~
a.cc:3:27: note: in definition of macro 'in'
    3 | #define in(x) int x; cin>>x;
      |                           ^
In file included from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54,
                 from /usr/in