/in/foo.cc: In function 'bool find(std::vector<int>, int)':
/in/foo.cc:5:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    5 |     for(int i=0;i<a.size();i++) if(a[i]==x) return true;
      |                 ~^~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:20:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |     for(int i=0;i<c.size();i++) cout<<c[i]<<" ";
      |                 ~^~~~~~~~~