/in/foo.c: In function 'main':
/in/foo.c:5:24: warning: unused variable 'z' [-Wunused-variable]
   int n,c=0,s=0,flag=1,z;
                        ^
/in/foo.c:5:17: warning: unused variable 'flag' [-Wunused-variable]
   int n,c=0,s=0,flag=1,z;
                 ^~~~
/in/foo.c:10:3: warning: array subscript is above array bounds [-Warray-bounds]
  y[13]=0;
  ~^~~~