foo.cc: In function 'int selectmin()':
foo.cc:10:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |         for(int i=0;i<f.size();i++){
      |                     ~^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:20:30: warning: variable 's1' set but not used [-Wunused-but-set-variable]
   20 |         long long int sum=0, s1=0;
      |                              ^~

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