Compilare: main.c: In function 'main': main.c:73:3: warning: 'return' with no value, in function returning non-void return; ^~~~~~ main.c:66:5: note: declared here int main() ^~~~ main.c: In function 'readGraphVertex': main.c:28:2: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%i %i %i", &(graph.numNodes), &(graph.numEdges), &(*s)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:40:3: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &e1, &e2); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~