foo.cc: In function 'int main()':
foo.cc:25:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |         for(int i=0;i<ve.size();++i){
      |                     ~^~~~~~~~~~
foo.cc:27:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |                 if(i!=ve.size()-1)
      |                    ~^~~~~~~~~~~~~

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