foo.cc: In function 'int main()':
foo.cc:33:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |         for(int i=0,j=0;i<x.size();i++)
      |                         ~^~~~~~~~~
foo.cc:58:66: warning: narrowing conversion of 'sz.std::vector<st>::size()' from 'std::vector<st>::size_type' {aka 'long unsigned int'} to 'long long int' [-Wnarrowing]
   58 |                         sz.push_back((st){-1,-1,-1,b[++j],sz.size(),'?'});
      |                                                           ~~~~~~~^~

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