foo.cc: In function 'int main()':
foo.cc:18:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   18 |     freopen("toy.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:19:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   19 |     freopen("toy.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:21:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |     scanf("%d", &t);
      |     ~~~~~^~~~~~~~~~
foo.cc:23:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |         scanf("%d %d", &n, &s);
      |         ~~~~~^~~~~~~~~~~~~~~~~

Found 10 testcases.
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