Language: C++

#include <bits/stdc++.h>
#define IOS ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define unsigned long long int
#define pb push_back
#define mp make_pair
#define f(i,x,n) for(ll i=x;i<n;i++)
#define fl(i,x,n) for(ll i=n;i>=x;i--)
#define mod (ll)1e9+7
#define print(x) cout<<x<<endl
#define vec vector<ll>
#define pai pair<ll, ll>
#define itr(it) :: iterator it
#define MAX (ll)1e16
#define MIN (ll)-1e16
#define X first
#define Y second
#define up upper_bound
#define lo lower_bound
using namespace std;
       ///////////   ///     ///   ///      ///   ////////////  ///      ///
       ///           ///     ///   ///      ///   ///      ///  ///      ///
       ///           ///     ///   ///      ///   ///      ///  ///      ///
       ///////////   ///////////   ///      ///   ////////////  ////////////
               ///   ///     ///   ///      ///   ///      ///  ///      ///
               ///   ///     ///   ///      ///   ///      ///  ///      ///
       ///////////   ///     ///   ////////////   ////////////  ///      ///
ll minn( ll a , ll b) 
{
    if(a>b)
        return b;
    return a;
}
ll maxx2( ll a , ll b)
{
    if(a>b)
        return a;
    return b;
}
ll maxx(ll a,ll b,ll c)
{
  return maxx2(a,maxx2(b,c));
}
ll gcdd(ll a, ll b)
{
    if(b==0)
        return a;
    else
        return gcdd(b,a%b);
}
ll dsum(ll n)
{
    ll sum=0;
    while(n>0)
    {
        sum+=n%10;
        n/=10;
    }
    return sum;
}
ll poww(ll a,ll b)
{
    if(b<=0)
        return 1;
    if(b==1)
        return a;
    if(b==2)
        return (a*a);
    else
        return poww(poww(a,b/2),2)*(poww(a,b%2));
}
ll sumsq(ll x,ll y,ll z)
{
    return (x-y)*(x-y)+(y-z)*(y-z)+(z-x)*(z-x);
} 
signed main() 
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    IOS;
    ll n;
    cin>>n;
    ll a[n],ans=1,f=0;
    f(i,0,n)
    {
        cin>>a[i];
        if(a[i]==0)
            f=1;
    }
    if(f==1)
    {
        cout<<0<<endl;
        return 0;
    }
    f(i,0,n)
    {
        ll x=ans;
        ans*=a[i];
        if((x>ans) || ans>1000000000000000000)
        {
            cout<<"-1"<<endl;
            return 0;
            break;
        }
    }
    cout<<ans<<endl;

    return 0;
}

Compiler output:
a.cc:27:1: error: 'll' does not name a type; did you mean 'lo'?
   27 | ll minn( ll a , ll b)
      | ^~
      | lo
a.cc:33:1: error: 'll' does not name a type; did you mean 'lo'?
   33 | ll maxx2( ll a , ll b)
      | ^~
      | lo
a.cc:39:1: error: 'll' does not name a type; did you mean 'lo'?
   39 | ll maxx(ll a,ll b,ll c)
      | ^~
      | lo
a.cc:43:1: error: 'll' does not name a type; did you mean 'lo'?
   43 | ll gcdd(ll a, ll b)
      | ^~
      | lo
a.cc:50:1: error: 'll' does not name a type; did you mean 'lo'?
   50 | ll dsum(ll n)
      | ^~
      | lo
a.cc:60:1: error: 'll' does not name a type; did you mean 'lo'?
   60 | ll poww(ll a,ll b)
      | ^~
      | lo
a.cc:71:1: error: 'll' does not name a type; did you mean 'lo'?
   71 | ll sumsq(ll x,ll y,ll z)
      | ^~
      | lo
a.cc: In function 'int main()':
a.cc:80:5: error: 'll' was not declared in this scope; did you mean 'lo'?
   80 |     ll n;
      |     ^~
      |     lo
a.cc:81:10: error: 'n' was not declared in this scope; did you mean 'yn'?
   81 |     cin>>n;
      |          ^
      |          yn
a.cc:82:7: error: expected ';' before 'a'
   82 |     ll a[n],ans=1,f=0;
      |       ^~
      |       ;
a.cc:83:7: error: expected ';' before 'i'
   83 |     f(i,0,n)
      |       ^
a.cc:6:25: note: in definition of macro 'f'
    6 | #define f(i,x,n) for(ll i=x;i<n;i++)
      |                         ^
a.cc:83:7: error: 'i' was not declared in this scope
   83 |     f(i,0,n)
      |       ^
a.cc:6:29: note: in definition of macro 'f'
    6 | #define f(i,x,n) for(ll i=x;i<n;i++)
      |                             ^
a.cc:85:14: error: 'a' was not declared in this scope
   85 |         cin>>a[i];
      |              ^
a.cc:87:13: error: 'f' was not declared in this scope
   87 |             f=1;
      |             ^
a.cc:89:8: error: 'f' was not declared in this scope
   89 |     if(f==1)
      |        ^
a.cc:94:7: error: expected ';' before 'i'
   94 |     f(i,0,n)
      |       ^
a.cc:6:25: note: in definition of macro 'f'
    6 | #define f(i,x,n) for(ll i=x;i<n;i++)
      |                         ^
a.cc:94:7: error: 'i' was not declared in this scope
   94 |     f(i,0,n)
      |       ^
a.cc:6:29: note: in definition of macro 'f'
    6 | #define f(i,x,n) for(ll i=x;i<n;i++)
      |                             ^
a.cc:96:11: error: expected ';' before 'x'
   96 |         ll x=ans;
      |           ^~
      |           ;
a.cc:97:9: error: 'ans' was not declared in this scope; did you mean 'abs'?
   97 |         ans*=a[i];
      |         ^~~
      |         abs
a.cc:97:14: error: 'a' was not declared in this scope
   97 |         ans*=a[i];
      |              ^
a.cc:98:13: error: 'x' was not declared in this scope
   98 |         if((x>ans) || ans>1000000000000000000)
      |             ^
a.cc:105:11: error: 'ans' was not declared in this scope; did you mean 'abs'?
  105 |     cout<<ans<<endl;
      |           ^~~
      |           abs