/in/foo.cc: In function 'int main()':
/in/foo.cc:7:8: warning: unused variable 'j' [-Wunused-variable]
  int i,j,k,l,n,maxx=-1;
        ^
/in/foo.cc:7:10: warning: unused variable 'k' [-Wunused-variable]
  int i,j,k,l,n,maxx=-1;
          ^
/in/foo.cc:7:12: warning: unused variable 'l' [-Wunused-variable]
  int i,j,k,l,n,maxx=-1;
            ^
/in/foo.cc:7:16: warning: unused variable 'maxx' [-Wunused-variable]
  int i,j,k,l,n,maxx=-1;
                ^~~~