foo.cc: In function 'int main()':
foo.cc:9:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
    9 |  freopen("boxline.in","r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:10:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   10 |  freopen("boxline.out","w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:20:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |         scanf("%d", &op);
      |         ~~~~~^~~~~~~~~~~
foo.cc:24:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |           scanf("%d%d", &X, &Y);
      |           ~~~~~^~~~~~~~~~~~~~~~

Found 10 testcases.
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