foo.c: In function 'main':
foo.c:8:9: warning: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    8 |         scanf_s("%d %d %d %d", &x1, &y1, &x2, &y2);
      |         ^~~~~~~
      |         scanf
foo.c:9:13: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
    9 |         s = abs(x2 - x1) + abs(y2 - y1);
      |             ^~~
foo.c:3:1: note: include '<stdlib.h>' or provide a declaration of 'abs'
    2 | #include <math.h>
  +++ |+#include <stdlib.h>
    3 | int min(int e, int f);
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: /tmp/cc8h82R2.o: in function `main':
foo.c:(.text.startup+0x26): undefined reference to `scanf_s'
collect2: error: ld returned 1 exit status

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