Compilare: user.cpp: In function ‘long int df(int)’: user.cpp:14:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:51:17: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘long int’ [-Wformat=] printf("%d",sol); ^