foo.cc: In function 'int main()':
foo.cc:21:21: warning: format '%d' expects argument of type 'int*', but argument 4 has type 'int' [-Wformat=]
   21 |         scanf("%d%d%d",&edge[i].x,&edge[i].y,edge[i].w);
      |                    ~^                        ~~~~~~~~~
      |                     |                                |
      |                     int*                             int
foo.cc:21:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |         scanf("%d%d%d",&edge[i].x,&edge[i].y,edge[i].w);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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