foo.c: In function 'main':
foo.c:18:9: warning: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
   18 |         scanf_s("%d",&n);
      |         ^~~~~~~
      |         scanf
foo.c:20:13: warning: unused variable 'sz' [-Wunused-variable]
   20 |         int sz = sizeof(a) / sizeof(a[0]);
      |             ^~
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: /tmp/ccPFz2fY.o: in function `main':
foo.c:(.text.startup+0x36): undefined reference to `scanf_s'
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: foo.c:(.text.startup+0x56): undefined reference to `scanf_s'
collect2: error: ld returned 1 exit status

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