foo.c:5:31: error: expected ';', ',' or ')' before '=' token
 int find(int s[],int n,int num=-9999)
                               ^
foo.c: In function 'main':
foo.c:28:10: warning: implicit declaration of function 'find' [-Wimplicit-function-declaration]
  int max=find(a,n,num);
          ^~~~
foo.c:23:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:26:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
   ^~~~~~~~~~~~~~~~~

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