foo.cc: In function 'int main()':
foo.cc:42:53: error: 'max' was not declared in this scope; did you mean 'std::max'?
   42 |                                                 ans=max(ans,os);
      |                                                     ^~~
      |                                                     std::max
In file included from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/algorithm:62,
                 from stdc++.h:65:
/nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/bits/stl_algo.h:3467:5: note: 'std::max' declared here
 3467 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~

Found 10 testcases.
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