foo.c: In function 'main':
foo.c:8:16: warning: implicit declaration of function 'gets_s'; did you mean 'gets'? [-Wimplicit-function-declaration]
    8 |         while (gets_s(s1) != NULL&& gets_s(s2) != NULL) {
      |                ^~~~~~
      |                gets
foo.c:8:27: warning: comparison between pointer and integer
    8 |         while (gets_s(s1) != NULL&& gets_s(s2) != NULL) {
      |                           ^~
foo.c:8:48: warning: comparison between pointer and integer
    8 |         while (gets_s(s1) != NULL&& gets_s(s2) != NULL) {
      |                                                ^~
foo.c:7:18: warning: unused variable 's' [-Wunused-variable]
    7 |         int t=0, s=0;
      |                  ^
foo.c:7:13: warning: unused variable 't' [-Wunused-variable]
    7 |         int t=0, s=0;
      |             ^
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: /tmp/ccv2zwTp.o: in function `main':
foo.c:(.text.startup+0x1b): undefined reference to `gets_s'
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: foo.c:(.text.startup+0x27): undefined reference to `Length'
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: foo.c:(.text.startup+0x36): undefined reference to `Length'
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: foo.c:(.text.startup+0x50): undefined reference to `gets_s'
collect2: error: ld returned 1 exit status

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