/in/foo.cc: In function 'int main()':
/in/foo.cc:8:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=1;i<strlen(a);i++) cout<<a[i];
               ~^~~~~~~~~~
/in/foo.cc:18:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i=0;i<v.size();i++) cout<<v[i];
                ~^~~~~~~~~
/in/foo.cc:22:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<v.size()-2;i++)
               ~^~~~~~~~~~~