foo.cc: In function 'int main()':
foo.cc:51:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   51 |         scanf("%d%d%d",&edge[i].x,&edge[i].y,&edge[i].w);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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