foo.c:1:10: error: #include expects "FILENAME" or <FILENAME>
    1 | #include _CRT_SECURE_NO_WARNINGS
      |          ^~~~~~~~~~~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:9:13: warning: variable 'b' set but not used [-Wunused-but-set-variable]
    9 |         int b[20] = { 0 };
      |             ^

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