foo.c: In function 'main':
foo.c:35:43: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
   35 |                         sum[j] = sum[j] + abs(b);
      |                                           ^~~
foo.c:3:1: note: include '<stdlib.h>' or provide a declaration of 'abs'
    2 | #include<math.h>
  +++ |+#include <stdlib.h>
    3 | int main()
foo.c:41:13: warning: 'sum' may be used uninitialized [-Wmaybe-uninitialized]
   41 |         int xmin = sum[min];
      |             ^~~~
foo.c:27:13: note: 'sum' declared here
   27 |         int sum[100000];
      |             ^~~
foo.c:14:19: warning: 'a' may be used uninitialized [-Wmaybe-uninitialized]
   14 |         min = max = a[1];
      |               ~~~~^~~~~~
foo.c:7:13: note: 'a' declared here
    7 |         int a[100000];
      |             ^

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