foo.cc: In function 'int find(std::vector<long long int>&, long long int)':
foo.cc:6:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    6 |  for(int i = 0;i < a.size();i++)if(a[i]==b)return i;
      |                ~~^~~~~~~~~~
foo.cc: In function 'void DIV(long long int, long long int)':
foo.cc:25:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |  for(int i = 0;i < s.size();i++)
      |                ~~^~~~~~~~~~
foo.cc:29:7: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |   if(i==s.size()-1&&k!=-1)cout<<')';
      |      ~^~~~~~~~~~~~

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