foo.c: In function 'main':
foo.c:16:18: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
   16 |    tmp[i]=tmp[i]+abs(a[i]-a[j]);
      |                  ^~~
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:9:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务