foo.c: In function 'main':
foo.c:27:11: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
   27 |   sum=sum+abs(a[i]-aveg);
      |           ^~~
foo.c:27:19: warning: 'abs' argument 1 promotes to 'double' where 'int' is expected in a call to built-in function declared without prototype [-Wbuiltin-declaration-mismatch]
   27 |   sum=sum+abs(a[i]-aveg);
      |               ~~~~^~~~~
<built-in>: note: built-in 'abs' declared here
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:10:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~

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