/in/foo.cc: In function 'void SPFA()':
/in/foo.cc:36:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int k=0;k<g[i].size();k++){
               ~^~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:70:27: warning: format '%d' expects argument of type 'int', but argument 2 has type 'll {aka long long int}' [-Wformat=]
      printf("%d\n",dist[i]);
                           ^