Compilare: user.cpp: In function ‘void heap_push()’: user.cpp:27:9: warning: unused variable ‘a’ [-Wunused-variable] int a,ll=L; ^ user.cpp: In function ‘int main()’: user.cpp:56:47: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d%d%d%d",&n,&edges,&A,&B,&C); ^ user.cpp:58:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d%d",&x,&y,&cost); ^