Compilare: user.cpp: In function ‘void solve(int, int, int, int, int, std::vector<std::vector<int> >&, std::vector<int>&)’: user.cpp:25:39: warning: suggest parentheses around ‘+’ inside ‘<<’ [-Wparentheses] if ((masca ^ bit) == (1 << nr_cif + 1) - 1) return; ^ user.cpp: In function ‘int main()’: user.cpp:47:24: warning: suggest parentheses around ‘+’ inside ‘<<’ [-Wparentheses] int index = 1 << cnt + 1; ^ user.cpp:42:13: warning: unused variable ‘sol’ [-Wunused-variable] long long sol = 0ll; ^