#include <mpi.h>

MPI_COomm graph_comm;
int nnodes=4;
int index[4]={1,3,5,7};
int edges[8]={1,3,0,2,1,3,0,2};
int reorder=1;
MPI_Graph_create(MPI_COMM_WORLD, nnodes, index, edges, reorder, graph_comm);

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#include <mpi.h>

MPI_COomm graph_comm;
int nnodes=4;
int index[4]={1,4,5,6};
int edges[6]={1,0,2,3,1,1};
int reorder=1;
MPI_Graph_create(MPI_COMM_WORLD, nnodes, index, edges, reorder, graph_comm);