foo.c: In function 'main':
foo.c:15:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   15 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:17:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c: In function 'gys':
foo.c:9:9: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
    9 |  return k;
      |         ^
foo.c: In function 'main':
foo.c:5:8: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
    5 |  int x,k;
      |        ^

[Hydro](https://hydro.ac)提供评测服务