foo.cc: In function 'void solve()':
foo.cc:21:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |     scanf("%d%d%d", &n, &m, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
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", p + i, w + i);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |         scanf("%d%d", &x, &y);
      |         ~~~~~^~~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:57:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   57 |     if (multi) scanf("%d", &_);
      |                ~~~~~^~~~~~~~~~

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