Compilare: main.cpp: In function 'std::vector<int> divizori(int)': main.cpp:25:20: warning: comparison of integer expressions of different signedness: 'ull' {aka 'long long unsigned int'} and 'int' [-Wsign-compare] 25 | for(ull d=1;d*d<=n;d++){ | ~~~^~~ main.cpp: In function 'void sol55(int)': main.cpp:38:22: warning: comparison of integer expressions of different signedness: 'ull' {aka 'long long unsigned int'} and 'int' [-Wsign-compare] 38 | for(ull a=b/2+1;a<b;a++){ | ~^~