foo.c: In function 'main':
foo.c:6:18: warning: format '%d' expects argument of type 'int', but argument 2 has type 'int *' [-Wformat=]
    6 |         printf("%d %d",&ci,&ei);
      |                 ~^     ~~~
      |                  |     |
      |                  int   int *
      |                 %ls
foo.c:6:21: warning: format '%d' expects argument of type 'int', but argument 3 has type 'int *' [-Wformat=]
    6 |         printf("%d %d",&ci,&ei);
      |                    ~^      ~~~
      |                     |      |
      |                     int    int *
      |                    %ls
foo.c:5:9: warning: unused variable 'n' [-Wunused-variable]
    5 |     int n,ci,ei;
      |         ^

[Hydro](https://hydro.ac)提供评测服务