/in/foo.cc: In function 'int main()':
/in/foo.cc:7:4: warning: statement has no effect [-Wunused-value]
   k>n;
   ~^~
/in/foo.cc:8:4: warning: statement has no effect [-Wunused-value]
   l>m;
   ~^~
/in/foo.cc:9:4: warning: statement has no effect [-Wunused-value]
   k>l;
   ~^~
/in/foo.cc:11:8: warning: 'k' is used uninitialized in this function [-Wuninitialized]
  cout<<k<<endl;
        ^