foo.c: In function 'main':
foo.c:12:9: warning: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
   12 |         scanf_s("%d %d",&ci,&ei);
      |         ^~~~~~~
      |         scanf
/nix/store/74y3751gsixaz9797ib0hp7c658sp1y5-binutils-2.40/bin/ld: /tmp/ccYpwkQT.o: in function `main':
foo.c:(.text.startup+0x60): undefined reference to `scanf_s'
collect2: error: ld returned 1 exit status

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