foo.cc: In function 'int main()':
foo.cc:49:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&x1,&y1);
  ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:50:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&x2,&y2);
  ~~~~~^~~~~~~~~~~~~~~~~
foo.cc: In function 'int Div(int*, int, int, int*)':
foo.cc:5:10: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int i,j,k;
          ^

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