Compilare: main.cpp: In function 'int main()': main.cpp:44:46: warning: format '%d' expects argument of type 'int', but argument 3 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=] fprintf (fout,"%d ",sol[j].size()); ^ main.cpp:45:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (l=0;l<sol[j].size();l++) ~^~~~~~~~~~~~~~ main.cpp:14:30: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&n,&k); ^