/in/foo.c: In function 'main':
/in/foo.c:7:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[300]' [-Wformat=]
  scanf("%s",&s);
          ^
/in/foo.c:8:16: error: 'n' undeclared (first use in this function)
  for(int i=0;i<n;i++)
                ^
/in/foo.c:8:16: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:33:12: error: lvalue required as left operand of assignment
     s[i+24]='y')
            ^