/in/foo.cc: In function 'int min1()':
/in/foo.cc:12:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<vi.size()-1;i++){
              ~^~~~~~~~~~~~
/in/foo.cc: In function 'int ou()':
/in/foo.cc:31:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<vi.size()-1&&j>0){
         ~^~~~~~~~~~~~
/in/foo.cc: In function 'int ji()':
/in/foo.cc:73:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=vi.size()-1;i>=vi.size()-vi.size()/2;i--){
                        ~^~~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc:76:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<vi.size()/2+1;i++){
              ~^~~~~~~~~~~~~~