foo.cc: In function 'int main()':
foo.cc:13:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |  scanf("%d%d",&m,&n);
      |  ~~~~~^~~~~~~~~~~~~~
foo.cc:16:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |   scanf("%d",&w[i]);
      |   ~~~~~^~~~~~~~~~~~
foo.cc:35:8: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   35 |  printf("%d\n",m - ans);
      |  ~~~~~~^~~~~~~~~~~~~~~~

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