foo.cc: In function 'int main()':
foo.cc:6:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |     scanf("%d%d", &v, &n);
      |     ~~~~~^~~~~~~~~~~~~~~~
foo.cc:8:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |         scanf("%d%d%d", &w[i], &p[i], &fa);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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