foo.cc:1:1: error: stray '##' in program
    1 | ##include <iostream>
      | ^~
foo.cc:1:3: error: 'include' does not name a type
    1 | ##include <iostream>
      |   ^~~~~~~
foo.cc: In function 'int main()':
foo.cc:5:1: error: 'cout' was not declared in this scope
    5 | cout<<"2"<<endl;
      | ^~~~
foo.cc:5:12: error: 'endl' was not declared in this scope
    5 | cout<<"2"<<endl;
      |            ^~~~

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