test.cpp:59: warning: 'bool operator==(const bigint&, const bigint&)' is already a friend of class 'bigint' test.cpp: In function 'bigint operator*(const bigint&, const bigint&)': test.cpp:340: warning: suggest parentheses around '&&' within '||' test.cpp: In function 'bigint operator*=(bigint&, const bigint&)': test.cpp:374: warning: suggest parentheses around '&&' within '||' test.cpp: In function 'std::istream& operator>>(std::istream&, bigint&)': test.cpp:542: warning: no return statement in function returning non-void test.cpp: In function 'std::ostream& operator<<(std::ostream&, const bigint&)': test.cpp:548: warning: no return statement in function returning non-void