foo.c: In function 'move':
foo.c:13:13: warning: unused variable 'flag' [-Wunused-variable]
   13 |         int flag = 0;
      |             ^~~~
foo.c: In function 'main':
foo.c:23:9: warning: implicit declaration of function 'gets_s'; did you mean 'gets'? [-Wimplicit-function-declaration]
   23 |         gets_s(a);
      |         ^~~~~~
      |         gets
/nix/store/3r87a2wq1w4l66wnsm7rqvy608mx23h6-binutils-2.40/bin/ld: /tmp/cccxF0DV.o: in function `main':
foo.c:(.text.startup+0xd): undefined reference to `gets_s'
/nix/store/3r87a2wq1w4l66wnsm7rqvy608mx23h6-binutils-2.40/bin/ld: foo.c:(.text.startup+0x19): undefined reference to `gets_s'
collect2: error: ld returned 1 exit status

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