foo.c: In function 'main':
foo.c:12:13: error: 'else' without a previous 'if'
   12 |             else if(x%2==0)
      |             ^~~~
foo.c:12:18: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   12 |             else if(x%2==0)
      |                  ^~
foo.c:14:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   14 |                 ++a;
      |                 ^~

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