Compilare: user.cpp: In function ‘void sets(std::vector<int>&)’: user.cpp:41:68: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] for (unsigned long long count = 0; count <= (1 << v.size() - 1 ) - 1; count ++) ^ user.cpp:41:76: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (unsigned long long count = 0; count <= (1 << v.size() - 1 ) - 1; count ++) ^ user.cpp:44:24: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (isSet (i, count)) ^