In file included from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/istream:39,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/sstream:38,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/complex:45,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ccomplex:39,
                 from stdc++.h:54:
In member function 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>]',
    inlined from 'int main()' at foo.cc:22:9:
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ostream:202:25: warning: 'b' may be used uninitialized [-Wmaybe-uninitialized]
  202 |       { return _M_insert(__n); }
      |                ~~~~~~~~~^~~~~
foo.cc: In function 'int main()':
foo.cc:7:27: note: 'b' was declared here
    7 |         int long long n,a,b;
      |                           ^
In member function 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>]',
    inlined from 'int main()' at foo.cc:20:9:
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ostream:202:25: warning: 'a' may be used uninitialized [-Wmaybe-uninitialized]
  202 |       { return _M_insert(__n); }
      |                ~~~~~~~~~^~~~~
foo.cc: In function 'int main()':
foo.cc:7:25: note: 'a' was declared here
    7 |         int long long n,a,b;
      |                         ^

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