foo.cc: In function 'int main()':
foo.cc:9:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |     scanf("%lld %lld",&tw,&n);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:13:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |         scanf("%lld",&w[i]);
      |         ~~~~~^~~~~~~~~~~~~~

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