foo.cc: In function 'int main()':
foo.cc:21:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |    for (int i=0;i<v[a[y]].size();i++)
      |                 ~^~~~~~~~~~~~~~~
foo.cc:33:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |     for (int i=0;i<v[a[x]].size();i++)
      |                  ~^~~~~~~~~~~~~~~
foo.cc:38:21: warning: 'ny' may be used uninitialized in this function [-Wmaybe-uninitialized]
   38 |     cout<<fabs(nx-ny)<<endl;
      |                     ^
foo.cc:38:21: warning: 'nx' may be used uninitialized in this function [-Wmaybe-uninitialized]

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