foo.c: In function 'main':
foo.c:12:24: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   12 |         if (a % 4 == 0 && a % 100 != 0 || a % 400 == 0)
      |             ~~~~~~~~~~~^~~~~~~~~~~~~~~
foo.c:11:8: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
   11 |     if (b == 2)
      |        ^

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