foo.cc: In function 'int main()':
foo.cc:22:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  freopen("blast.in", "r", stdin);
  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:23:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  freopen("blast.out", "w", stdout);
  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:24:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s", a + 1);
  ~~~~~^~~~~~~~~~~~~
foo.cc:25:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s", b + 1);
  ~~~~~^~~~~~~~~~~~~
foo.cc:28:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &k);
  ~~~~~^~~~~~~~~~

自豪的采用 HydroJudger 进行评测(github.com/hydro-dev/HydroJudger)

{"receive":"2020-05-30T12:59:23.390Z","handle":"2020-05-30T12:59:23.390Z","cache_start":"2020-05-30T12:59:23.397Z","read_cases":"2020-05-30T12:59:23.534Z","judge":"2020-05-30T12:59:23.540Z","done":"2020-05-30T12:59:23.942Z"}