Language: C++

#include<iostream>
using namespace std;

int main (){
int a, b;
cin>> a >> b;

if ( a < b ){
cout << ???a < b??? << endl;
}
else if ( a > b ) {
cout << ???a > b??? << endl;
} else {
cout << ???a == b??? << endl;
}

return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:9:9: error: expected primary-expression before '?' token
    9 | cout << ???a < b??? << endl;
      |         ^
a.cc:9:10: error: expected primary-expression before '?' token
    9 | cout << ???a < b??? << endl;
      |          ^
a.cc:9:11: error: expected primary-expression before '?' token
    9 | cout << ???a < b??? << endl;
      |           ^
a.cc:9:18: error: expected primary-expression before '?' token
    9 | cout << ???a < b??? << endl;
      |                  ^
a.cc:9:19: error: expected primary-expression before '?' token
    9 | cout << ???a < b??? << endl;
      |                   ^
a.cc:9:21: error: expected primary-expression before '<<' token
    9 | cout << ???a < b??? << endl;
      |                     ^~
a.cc:9:28: error: expected ':' before ';' token
    9 | cout << ???a < b??? << endl;
      |                            ^
      |                            :
a.cc:9:28: error: expected primary-expression before ';' token
a.cc:9:28: error: expected ':' before ';' token
    9 | cout << ???a < b??? << endl;
      |                            ^
      |                            :
a.cc:9:28: error: expected primary-expression before ';' token
a.cc:9:28: error: expected ':' before ';' token
    9 | cout << ???a < b??? << endl;
      |                            ^
      |                            :
a.cc:9:28: error: expected primary-expression before ';' token
a.cc:9:28: error: expected ':' before ';' token
    9 | cout << ???a < b??? << endl;
      |                            ^
      |                            :
a.cc:9:28: error: expected primary-expression before ';' token
a.cc:9:28: error: expected ':' before ';' token
    9 | cout << ???a < b??? << endl;
      |                            ^
      |                            :
a.cc:9:28: error: expected primary-expression before ';' token
a.cc:9:28: error: expected ':' before ';' token
    9 | cout << ???a < b??? << endl;
      |                            ^
      |                            :
a.cc:9:28: error: expected primary-expression before ';' token
a.cc:12:9: error: expected primary-expression before '?' token
   12 | cout << ???a > b??? << endl;
      |         ^
a.cc:12:10: error: expected primary-expression before '?' token
   12 | cout << ???a > b??? << endl;
      |          ^
a.cc:12:11: error: expected primary-expression before '?' token
   12 | cout << ???a > b??? << endl;
      |           ^
a.cc:12:18: error: expected primary-expression before '?' token
   12 | cout << ???a > b??? << endl;
      |                  ^
a.cc:12:19: error: expected primary-expression before '?' token
   12 | cout << ???a > b??? << endl;
      |                   ^
a.cc:12:21: error: expected primary-expression before '<<' token
   12 | cout << ???a > b??? << endl;
      |                     ^~
a.cc:12:28: error: expected ':' before ';' token
   12 | cout << ???a > b??? << endl;
      |                            ^
      |                            :
a.cc:12:28: error: expected primary-expression before ';' token
a.cc:12:28: error: expected ':' before ';' token
   12 | cout << ???a > b??? << endl;
      |                            ^
      |                            :
a.cc:12:28: error: expected primary-expression before ';' token
a.cc:12:28: error: expected ':' before ';' token
   12 | cout << ???a > b??? << endl;
      |                            ^
      |                            :
a.cc:12:28: error: expected primary-expression before ';' token
a.cc:12:28: error: expected ':' before ';' token
   12 | cout << ???a > b??? << endl;
      |                            ^
      |                            :
a.cc:12:28: error: expected primary-expression before ';' token
a.cc:12:28: error: expected ':' before ';' token
   12 | cout << ???a > b??? << endl;
      |                            ^
      |                            :
a.cc:12:28: error: expected primary-expression before ';' token
a.cc:12:28: error: expected ':' before ';' token
   12 | cout << ???a > b??? << endl;
      |                            ^
      |                            :
a.cc:12:28: error: expected primary-expression before ';' token
a.cc:14:9: error: expected primary-expression before '?' token
   14 | cout << ???a == b??? << endl;
      |         ^
a.cc:14:10: error: expected primary-expression before '?' token
   14 | cout << ???a == b??? << endl;
      |          ^
a.cc:14:11: error: expected primary-expression before '?' token
   14 | cout << ???a == b??? << endl;
      |           ^
a.cc:14:19: error: expected primary-expression before '?' token
   14 | cout << ???a == b??? << endl;
      |                   ^
a.cc:14:20: error: expected primary-expression before '?' token
   14 | cout << ???a == b??? << endl;
      |                    ^
a.cc:14:22: error: expected primary-expression before '<<' token
   14 | cout << ???a == b??? << endl;
      |                      ^~
a.cc:14:29: error: expected ':' before ';' token
   14 | cout << ???a == b??? << endl;
      |                             ^
      |                             :
a.cc:14:29: error: expected primary-expression before ';' token
a.cc:14:29: error: expected ':' before ';' token
   14 | cout << ???a == b??? << endl;
      |                             ^
      |                             :
a.cc:14:29: error: expected primary-expression before ';' token
a.cc:14:29: error: expected ':' before ';' token
   14 | cout << ???a == b??? << endl;
      |                             ^
      |                             :
a.cc:14:29: error: expected primary-expression before ';' token
a.cc:14:29: error: expected ':' before ';' token
   14 | cout << ???a == b??? << endl;
      |                             ^
      |                             :
a.cc:14:29: error: expected primary-expression before ';' token
a.cc:14:29: error: expected ':' before ';' token
   14 | cout << ???a == b??? << endl;
      |                             ^
      |                             :
a.cc:14:29: error: expected primary-expression before ';' token
a.cc:14:29: error: expected ':' before ';' token
   14 | cout << ???a == b??? << endl;
      |                             ^
      |                             :
a.cc:14:29: error: expected primary-expression before ';' token