foo.c: In function 'main':
foo.c:51:13: warning: array subscript -2 is below array bounds of 'int[100]' [-Warray-bounds]
   51 |             printf("%d", b[c-2]);
      |             ^~~~~~~~~~~~~~~~~~~~
foo.c:15:13: note: while referencing 'b'
   15 |         int b[100],c=0;
      |             ^

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