/in/foo.cc: In function 'int main()':
/in/foo.cc:6:10: warning: statement has no effect [-Wunused-value]
     for(x>=1;x<=n;x++);
         ~^~~
/in/foo.cc:7:10: warning: statement has no effect [-Wunused-value]
     for(y>=1;y<=n;y++);
         ~^~~
/in/foo.cc:16:21: warning: format '%d' expects argument of type 'int', but argument 2 has type 'int*' [-Wformat=]
     printf("%d\n",&k);}
                     ^
/in/foo.cc:6:15: warning: 'x' is used uninitialized in this function [-Wuninitialized]
     for(x>=1;x<=n;x++);
              ~^~~
/in/foo.cc:6:15: warning: 'n' is used uninitialized in this function [-Wuninitialized]