Language: C++

#include <iostream>
using namespace std;
   int a,b;
   int main(){
  cin>>a>>b;
   cout<<"a+b"(???)<<endl;
   cout<<"a-b"(???)<<endl;
   cout<<"a*b"(???)<<endl;
   cout<<"a/b"(???)<<endl;
  return 0;
}

Compiler output:
a.cc:6:17: warning: trigraph ??) ignored, use -trigraphs to enable [-Wtrigraphs]
    6 |    cout<<"a+b"(???)<<endl;
a.cc:7:17: warning: trigraph ??) ignored, use -trigraphs to enable [-Wtrigraphs]
    7 |    cout<<"a-b"(???)<<endl;
a.cc:8:17: warning: trigraph ??) ignored, use -trigraphs to enable [-Wtrigraphs]
    8 |    cout<<"a*b"(???)<<endl;
a.cc:9:17: warning: trigraph ??) ignored, use -trigraphs to enable [-Wtrigraphs]
    9 |    cout<<"a/b"(???)<<endl;
a.cc: In function 'int main()':
a.cc:6:16: error: expected primary-expression before '?' token
    6 |    cout<<"a+b"(???)<<endl;
      |                ^
a.cc:6:17: error: expected primary-expression before '?' token
    6 |    cout<<"a+b"(???)<<endl;
      |                 ^
a.cc:6:18: error: expected primary-expression before '?' token
    6 |    cout<<"a+b"(???)<<endl;
      |                  ^
a.cc:6:19: error: expected primary-expression before ')' token
    6 |    cout<<"a+b"(???)<<endl;
      |                   ^
a.cc:6:19: error: expected ':' before ')' token
    6 |    cout<<"a+b"(???)<<endl;
      |                   ^
      |                   :
a.cc:6:19: error: expected primary-expression before ')' token
a.cc:6:19: error: expected ':' before ')' token
    6 |    cout<<"a+b"(???)<<endl;
      |                   ^
      |                   :
a.cc:6:19: error: expected primary-expression before ')' token
a.cc:6:19: error: expected ':' before ')' token
    6 |    cout<<"a+b"(???)<<endl;
      |                   ^
      |                   :
a.cc:6:19: error: expected primary-expression before ')' token
a.cc:6:19: error: expression cannot be used as a function
a.cc:7:16: error: expected primary-expression before '?' token
    7 |    cout<<"a-b"(???)<<endl;
      |                ^
a.cc:7:17: error: expected primary-expression before '?' token
    7 |    cout<<"a-b"(???)<<endl;
      |                 ^
a.cc:7:18: error: expected primary-expression before '?' token
    7 |    cout<<"a-b"(???)<<endl;
      |                  ^
a.cc:7:19: error: expected primary-expression before ')' token
    7 |    cout<<"a-b"(???)<<endl;
      |                   ^
a.cc:7:19: error: expected ':' before ')' token
    7 |    cout<<"a-b"(???)<<endl;
      |                   ^
      |                   :
a.cc:7:19: error: expected primary-expression before ')' token
a.cc:7:19: error: expected ':' before ')' token
    7 |    cout<<"a-b"(???)<<endl;
      |                   ^
      |                   :
a.cc:7:19: error: expected primary-expression before ')' token
a.cc:7:19: error: expected ':' before ')' token
    7 |    cout<<"a-b"(???)<<endl;
      |                   ^
      |                   :
a.cc:7:19: error: expected primary-expression before ')' token
a.cc:7:19: error: expression cannot be used as a function
a.cc:8:16: error: expected primary-expression before '?' token
    8 |    cout<<"a*b"(???)<<endl;
      |                ^
a.cc:8:17: error: expected primary-expression before '?' token
    8 |    cout<<"a*b"(???)<<endl;
      |                 ^
a.cc:8:18: error: expected primary-expression before '?' token
    8 |    cout<<"a*b"(???)<<endl;
      |                  ^
a.cc:8:19: error: expected primary-expression before ')' token
    8 |    cout<<"a*b"(???)<<endl;
      |                   ^
a.cc:8:19: error: expected ':' before ')' token
    8 |    cout<<"a*b"(???)<<endl;
      |                   ^
      |                   :
a.cc:8:19: error: expected primary-expression before ')' token
a.cc:8:19: error: expected ':' before ')' token
    8 |    cout<<"a*b"(???)<<endl;
      |                   ^
      |                   :
a.cc:8:19: error: expected primary-expression before ')' token
a.cc:8:19: error: expected ':' before ')' token
    8 |    cout<<"a*b"(???)<<endl;
      |                   ^
      |                   :
a.cc:8:19: error: expected primary-expression before ')' token
a.cc:8:19: error: expression cannot be used as a function
a.cc:9:16: error: expected primary-expression before '?' token
    9 |    cout<<"a/b"(???)<<endl;
      |                ^
a.cc:9:17: 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:9:19: error: expected ':' before ')' token
    9 |    cout<<"a/b"(???)<<endl;
      |                   ^
      |                   :
a.cc:9:19: error: expected primary-expression before ')' token
a.cc:9:19: error: expected ':' before ')' token
    9 |    cout<<"a/b"(???)<<endl;
      |                   ^
      |                   :
a.cc:9:19: error: expected primary-expression before ')' token
a.cc:9:19: error: expected ':' before ')' token
    9 |    cout<<"a/b"(???)<<endl;
      |                   ^
      |                   :
a.cc:9:19: error: expected primary-expression before ')' token
a.cc:9:19: error: expression cannot be used as a function