foo.cc:14:6: error: expected unqualified-id before 'if'
   14 |      if(sum==x)
      |      ^~
foo.cc:18:6: error: expected unqualified-id before 'else'
   18 |      else
      |      ^~~~
foo.cc:22:6: error: expected unqualified-id before 'return'
   22 |      return 0;
      |      ^~~~~~
foo.cc:23:6: error: expected declaration before '}' token
   23 |      }
      |      ^

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