Compilare: main.c: In function 'readFile': main.c:29:2: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf( f, "%d %d", &N, &M ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:44:3: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf( f, "%d %d %d", &A, &B, &C ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:27:10: warning: 'graph.costMatrix' may be used uninitialized in this function [-Wmaybe-uninitialized] return graph; ^~~~~