foo.cc: In function 'int main()':
foo.cc:37:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |  scanf("%d %d %d", &n, &m, &s);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:40:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |   scanf("%d %d %d", &a, &b, &c);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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