/in/foo.c: In function 'main':
/in/foo.c:34:2: error: expected ';' before 'int'
  int j=1;
  ^~~
/in/foo.c:35:8: error: 'j' undeclared (first use in this function)
  for ( j=1 ;j<n-1 ;j++)
        ^
/in/foo.c:35:8: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:16:7: warning: variable 'ch' set but not used [-Wunused-but-set-variable]
  char ch='i';
       ^~