foo.cc: In function 'void Div(int, int)':
foo.cc:59:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |  for (int i = index; i < s.length(); i++)
      |                      ~~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:67:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   67 |  scanf("%d%d", &x1, &y1);
      |  ~~~~~^~~~~~~~~~~~~~~~~~
foo.cc:68:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   68 |  scanf("%d%d", &x2, &y2);
      |  ~~~~~^~~~~~~~~~~~~~~~~~

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