Compilare: main.cpp: In function 'std::ostream& operator<<(std::ostream&, const mat&)': main.cpp:72:5: warning: no return statement in function returning non-void [-Wreturn-type] 72 | } | ^ main.cpp: In function 'mat exp(mat, long long int)': main.cpp:80:19: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses] 80 | if (e & 1 == 1) | ~~^~~~