foo.c: In function 'main':
foo.c:28:9: warning: 'a' may be used uninitialized [-Wmaybe-uninitialized]
   28 |         printf("%d",a[0]);
      |         ^~~~~~~~~~~~~~~~~
foo.c:10:13: note: 'a' declared here
   10 |         int a[100000], b[100000];
      |             ^

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