/in/foo.cc: In function 'int main()':
/in/foo.cc:23:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(i<v1.size()&&j<v2.size())
        ~^~~~~~~~~~
/in/foo.cc:23:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(i<v1.size()&&j<v2.size())
                     ~^~~~~~~~~~
/in/foo.cc:30:8: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(;i<v1.size();i++)
       ~^~~~~~~~~~
/in/foo.cc:32:8: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(;j<v2.size();j++)
       ~^~~~~~~~~~
/in/foo.cc:9:12: warning: unused variable 't' [-Wunused-variable]
  int x,i,n,t,j;
            ^