foo.c: In function 'main':
foo.c:4:2: warning: implicit declaration of function 'scanf_s' [-Wimplicit-function-declaration]
    4 |  scanf_s("%d", &n);
      |  ^~~~~~~
foo.c:13:5: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
   13 |     printf("%d %d\n", i, j);
      |     ^~~~~~
foo.c:13:5: warning: incompatible implicit declaration of built-in function 'printf'
foo.c:1:1: note: include '<stdio.h>' or provide a declaration of 'printf'
  +++ |+#include <stdio.h>
    1 | int main()
/usr/bin/ld: /tmp/cch2Nf3f.o: in function `main':
foo.c:(.text.startup+0x35): undefined reference to `scanf_s'
collect2: error: ld returned 1 exit status

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