Language: C++

#include <iostream>
using namespace std;
int main()
{
   ??int a[10000];
    int count = 0;
??   for (; count < 10000; count++)
??   {
      ????int x;
   ????   cin >> x;
????      if (x == 0) break;
   ????   a[count] = x;
    }

??   for (int j = 0; j < count; j++)
   ??    cout << "Case " << j+1 << ": " << a[j] << endl;
??   }
   ??return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:5:4: error: expected primary-expression before '?' token
    5 |    ??int a[10000];
      |    ^
a.cc:5:5: error: expected primary-expression before '?' token
    5 |    ??int a[10000];
      |     ^
a.cc:5:6: error: expected primary-expression before 'int'
    5 |    ??int a[10000];
      |      ^~~
a.cc:5:6: error: expected ':' before 'int'
    5 |    ??int a[10000];
      |      ^~~
      |      :
a.cc:5:6: error: expected primary-expression before 'int'
    5 |    ??int a[10000];
      |      ^~~
a.cc:5:6: error: expected ':' before 'int'
    5 |    ??int a[10000];
      |      ^~~
      |      :
a.cc:5:6: error: expected primary-expression before 'int'
    5 |    ??int a[10000];
      |      ^~~
a.cc:7:1: error: expected primary-expression before '?' token
    7 | ??   for (; count < 10000; count++)
      | ^
a.cc:7:2: error: expected primary-expression before '?' token
    7 | ??   for (; count < 10000; count++)
      |  ^
a.cc:7:6: error: expected primary-expression before 'for'
    7 | ??   for (; count < 10000; count++)
      |      ^~~
a.cc:7:3: error: expected ':' before 'for'
    7 | ??   for (; count < 10000; count++)
      |   ^  ~~~
      |   :
a.cc:7:6: error: expected primary-expression before 'for'
    7 | ??   for (; count < 10000; count++)
      |      ^~~
a.cc:7:3: error: expected ':' before 'for'
    7 | ??   for (; count < 10000; count++)
      |   ^  ~~~
      |   :
a.cc:7:6: error: expected primary-expression before 'for'
    7 | ??   for (; count < 10000; count++)
      |      ^~~
a.cc:7:35: error: expected ';' before ')' token
    7 | ??   for (; count < 10000; count++)
      |                                   ^
      |                                   ;
a.cc:15:1: error: expected primary-expression before '?' token
   15 | ??   for (int j = 0; j < count; j++)
      | ^
a.cc:15:2: error: expected primary-expression before '?' token
   15 | ??   for (int j = 0; j < count; j++)
      |  ^
a.cc:15:6: error: expected primary-expression before 'for'
   15 | ??   for (int j = 0; j < count; j++)
      |      ^~~
a.cc:15:3: error: expected ':' before 'for'
   15 | ??   for (int j = 0; j < count; j++)
      |   ^  ~~~
      |   :
a.cc:15:6: error: expected primary-expression before 'for'
   15 | ??   for (int j = 0; j < count; j++)
      |      ^~~
a.cc:15:3: error: expected ':' before 'for'
   15 | ??   for (int j = 0; j < count; j++)
      |   ^  ~~~
      |   :
a.cc:15:6: error: expected primary-expression before 'for'
   15 | ??   for (int j = 0; j < count; j++)
      |      ^~~
a.cc:15:22: error: 'j' was not declared in this scope
   15 | ??   for (int j = 0; j < count; j++)
      |                      ^
a.cc:17:1: error: expected primary-expression before '?' token
   17 | ??   }
      | ^
a.cc:17:2: error: expected primary-expression before '?' token
   17 | ??   }
      |  ^
a.cc:17:6: error: expected primary-expression before '}' token
   17 | ??   }
      |      ^
a.cc:17:3: error: expected ':' before '}' token
   17 | ??   }
      |   ^  ~
      |   :
a.cc:17:6: error: expected primary-expression before '}' token
   17 | ??   }
      |      ^
a.cc:17:3: error: expected ':' before '}' token
   17 | ??   }
      |   ^  ~
      |   :
a.cc:17:6: error: expected primary-expression before '}' token
   17 | ??   }
      |      ^
a.cc: At global scope:
a.cc:18:4: error: expected unqualified-id before '?' token
   18 |    ??return 0;
      |    ^
a.cc:19:1: error: expected declaration before '}' token
   19 | }
      | ^