Language: C++

#include <iostream>
using namespace std;
int main(){
int n,c = 1;
while(n != 0){
  cin >> n;
  cout << ???Case ??? << c << ???: ??? << n <<endl;
  c++;
 }
 Return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:7:11: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |           ^
a.cc:7:12: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |            ^
a.cc:7:13: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |             ^
a.cc:7:14: error: 'Case' was not declared in this scope
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |              ^~~~
a.cc:7:20: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                    ^
a.cc:7:21: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                     ^
a.cc:7:23: error: expected primary-expression before '<<' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                       ^~
a.cc:7:31: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                               ^
a.cc:7:32: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                ^
a.cc:7:33: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                 ^
a.cc:7:36: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                    ^
a.cc:7:37: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                     ^
a.cc:7:38: error: expected primary-expression before '?' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                      ^
a.cc:7:40: error: expected primary-expression before '<<' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                        ^~
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:7:51: error: expected ':' before ';' token
    7 |   cout << ???Case ??? << c << ???: ??? << n <<endl;
      |                                                   ^
      |                                                   :
a.cc:7:51: error: expected primary-expression before ';' token
a.cc:10:2: error: 'Return' was not declared in this scope
   10 |  Return 0;
      |  ^~~~~~