Compilare: user.cpp: In function ‘int main()’: user.cpp:42:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<fathers[k].size(); i++) ^ user.cpp:54:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<fathers[0].size();i++) ^ user.cpp:18:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&V,&E); ^ user.cpp:24:41: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d%d",&x,&y,&cost); ^