foo.c: In function 'main':
foo.c:6:9: warning: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    6 |         scanf_s("%d %d %d", &t1h, &t1m, &t1s);
      |         ^~~~~~~
      |         scanf
foo.c:13:13: warning: statement with no effect [-Wunused-value]
   13 |         t2h > t1h;
      |         ~~~~^~~~~
foo.c:14:13: warning: statement with no effect [-Wunused-value]
   14 |         t2m >= t1m;
      |         ~~~~^~~~~~
foo.c:15:13: warning: statement with no effect [-Wunused-value]
   15 |         t2s >= t1s;
      |         ~~~~^~~~~~
foo.c:20:20: warning: format '%lld' expects argument of type 'long long int', but argument 2 has type 'int' [-Wformat=]
   20 |         printf("%lld\n", thms);
      |                 ~~~^     ~~~~
      |                    |     |
      |                    |     int
      |                    long long int
      |                 %d
/nix/store/j2gmfdd29cp3rcvghmn1a5kgcnmf8myp-binutils-2.40/bin/ld: /tmp/cckGYxdp.o: in function `main':
foo.c:(.text.startup+0x1b): undefined reference to `scanf_s'
/nix/store/j2gmfdd29cp3rcvghmn1a5kgcnmf8myp-binutils-2.40/bin/ld: foo.c:(.text.startup+0x36): undefined reference to `scanf_s'
collect2: error: ld returned 1 exit status

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