foo.cc: In function 'long long int Dijkstra()':
foo.cc:44:28: warning: overflow in implicit constant conversion [-Woverflow]
  memset(dis,inf,sizeof(dis));
                            ^
foo.cc: In function 'int main()':
foo.cc:71:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld%lld%lld%lld",&t,&n,&cost,&m);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:74:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld%lld%lld",&u,&v,&w);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:78:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld",&d);
  ~~~~~^~~~~~~~~~~
foo.cc:80:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld%lld%lld",&a[i].p,&a[i].s,&a[i].e);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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