foo.cc: In function 'int main()':
foo.cc:26:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<g[f.x].size();i++){
               ~^~~~~~~~~~~~~~
foo.cc:11:8: warning: unused variable 'm' [-Wunused-variable]
  int n,m,a,b,c;
        ^
foo.cc:12:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
foo.cc:14:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&dis[i]);
   ~~~~~^~~~~~~~~~~~~~

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